Scholars@Duke
Stephanie Padilla

Stephanie Padilla

Instructor in the Nicholas School of the Environment
Environmental Sciences and Policy

Selected Publications

EthoCRED: a framework to guide reporting and evaluation of the relevance and reliability of behavioural ecotoxicity studies.

Journal Article Biological reviews of the Cambridge Philosophical Society · October 2024 Behavioural analysis has been attracting significant attention as a broad indicator of sub-lethal toxicity and has secured a place as an important subdiscipline in ecotoxicology. Among the most notable characteristics of behavioural research, compared to o ... Full text Cite

Using Zebrafish to Screen Developmental Toxicity of Per- and Polyfluoroalkyl Substances (PFAS).

Journal Article Toxics · July 2024 Per- and polyfluoroalkyl substances (PFAS) are found in many consumer and industrial products. While some PFAS, notably perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are developmentally toxic in mammals, the vast majority of PFAS h ... Full text Cite

A Comparison of In Vitro Points of Departure with Human Blood Levels for Per- and Polyfluoroalkyl Substances (PFAS).

Journal Article Toxics · April 2024 Per- and polyfluoroalkyl substances (PFAS) are widely used, and their fluorinated state contributes to unique uses and stability but also long half-lives in the environment and humans. PFAS have been shown to be toxic, leading to immunosuppression, cancer, ... Full text Cite

Burn pit-related smoke causes developmental and behavioral toxicity in zebrafish: Influence of material type and emissions chemistry.

Journal Article Heliyon · April 2024 Combustion of mixed materials during open air burning of refuse or structural fires in the wildland urban interface produces emissions that worsen air quality, contaminate rivers and streams, and cause poor health outcomes including developmental effects. ... Full text Cite

Influence of Methylene Blue or Dimethyl Sulfoxide on Larval Zebrafish Development and Behavior.

Journal Article Zebrafish · August 2023 The use of larval zebrafish developmental testing and assessment, specifically larval zebrafish locomotor activity, has been recognized as a higher throughput testing strategy to identify developmentally toxic and neurotoxic chemicals. There are, however, ... Full text Cite

Inconsistencies in variable reporting and methods in larval zebrafish behavioral assays.

Journal Article Neurotoxicology and teratology · March 2023 New approaches in developmental neurotoxicity (DNT) screening are needed due to the tens of thousands of chemicals requiring hazard assessments. Zebrafish (Danio rerio) are an alternative vertebrate model for DNT testing, but without a standardized protoco ... Full text Cite

An expert-driven literature review of "negative" chemicals for developmental neurotoxicity (DNT) in vitro assay evaluation.

Journal Article Neurotoxicology and teratology · September 2022 To date, approximately 200 chemicals have been tested in US Environmental Protection Agency (EPA) or Organization for Economic Co-operation and Development (OECD) developmental neurotoxicity (DNT) guideline studies, leaving thousands of chemicals without t ... Full text Cite

Developmental Neurotoxicity and Behavioral Screening in Larval Zebrafish with a Comparison to Other Published Results.

Journal Article Toxics · May 2022 With the abundance of chemicals in the environment that could potentially cause neurodevelopmental deficits, there is a need for rapid testing and chemical screening assays. This study evaluated the developmental toxicity and behavioral effects of 61 chemi ... Full text Cite

Implementation of Zebrafish Ontologies for Toxicology Screening.

Journal Article Frontiers in toxicology · January 2022 Toxicological evaluation of chemicals using early-life stage zebrafish (Danio rerio) involves the observation and recording of altered phenotypes. Substantial variability has been observed among researchers in phenotypes reported from similar studie ... Full text Cite

The utility of alternative models in particulate matter air pollution toxicology.

Journal Article Current research in toxicology · January 2022 Exposure to particulate matter (PM) air pollution increases risk of adverse human health effects. As more attention is brought to bear on the problem of PM, traditional mammalian in vivo models struggle to keep up with the risk assessment challenges ... Full text Cite

Using zebrafish to assess developmental neurotoxicity

Chapter · January 1, 2022 It is widely accepted that the developing nervous system is especially vulnerable to a variety of chemicals, including drugs and environmental contaminants; however our understanding of the risks from chemical exposures during development is rudimentary. Z ... Full text Cite

Zebrafish irritant responses to wildland fire-related biomass smoke are influenced by fuel type, combustion phase, and byproduct chemistry.

Journal Article Journal of toxicology and environmental health. Part A · August 2021 Human exposure to wildfire-derived particulate matter (PM) is linked to adverse health outcomes; however, little is known regarding the influence of biomass fuel type and burn conditions on toxicity. The aim of this study was to assess the irritant potenti ... Full text Cite

The Role of Behavioral Ecotoxicology in Environmental Protection.

Journal Article Environmental science & technology · May 2021 For decades, we have known that chemicals affect human and wildlife behavior. Moreover, due to recent technological and computational advances, scientists are now increasingly aware that a wide variety of contaminants and other environmental stressors adve ... Full text Cite

Assessment of Larval Zebrafish Locomotor Activity for Developmental Neurotoxicity Screening

Chapter · January 1, 2021 Animal behavior has long been recognized as an informative endpoint for assessing effects of chemicals on the developing nervous system. Previous laboratory animal tests to screen and prioritize chemicals for developmental neurotoxicity have not met growin ... Full text Cite

The zebrafish (Danio rerio) model in toxicity testing

Chapter · January 1, 2020 Zebrafish have become a popular model for both human and ecological toxicity assessments. This chapter discusses the scientific reasons for that popularity; describing many examples of similarities between zebrafish and mammalian function and development; ... Full text Cite

The Next Generation Blueprint of Computational Toxicology at the U.S. Environmental Protection Agency.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · June 2019 The U.S. Environmental Protection Agency (EPA) is faced with the challenge of efficiently and credibly evaluating chemical safety often with limited or no available toxicity data. The expanding number of chemicals found in commerce and the environment, cou ... Full text Cite

High-Throughput Video Processing of Heart Rate Responses in Multiple Wild-type Embryonic Zebrafish per Imaging Field.

Journal Article Scientific reports · January 2019 Heart rate assays in wild-type zebrafish embryos have been limited to analysis of one embryo per video/imaging field. Here we present for the first time a platform for high-throughput derivation of heart rate from multiple zebrafish (Danio rerio) embryos p ... Full text Cite

Characterizing sources of variability in zebrafish embryo screening protocols.

Journal Article ALTEX · January 2019 There is a need for fast, efficient, and cost-effective hazard identification and characterization of chemical hazards. This need is generating increased interest in the use of zebrafish embryos as both a screening tool and an alternative to mammalian test ... Full text Cite

Biomarkers of Toxicity in Zebrafish

Chapter · January 1, 2019 Given that zebrafish have now become an accepted model for toxicological studies in both the human health and ecological communities, this chapter takes stock of the status of biomarkers of toxicity that have been proposed for the zebrafish model. Most of ... Full text Cite

Zebrafish Locomotor Responses Reveal Irritant Effects of Fine Particulate Matter Extracts and a Role for TRPA1.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · February 2018 Exposure to fine particulate matter (PM) air pollution causes adverse cardiopulmonary outcomes. Yet, the limited capacity to readily identify contributing PM sources and associated PM constituents in any given ambient air shed impedes risk assessment effor ... Full text Cite

Screening for angiogenic inhibitors in zebrafish to evaluate a predictive model for developmental vascular toxicity.

Journal Article Reproductive toxicology (Elmsford, N.Y.) · June 2017 Chemically-induced vascular toxicity during embryonic development may cause a wide range of adverse effects. To identify putative vascular disrupting chemicals (pVDCs), a predictive pVDC signature was constructed from 124 U.S. EPA ToxCast high-throughput s ... Full text Cite

Evaluating the zebrafish embryo toxicity test for pesticide hazard screening.

Journal Article Environmental toxicology and chemistry · May 2017 Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictiv ... Full text Cite

Reference compounds for alternative test methods to indicate developmental neurotoxicity (DNT) potential of chemicals: example lists and criteria for their selection and use.

Journal Article ALTEX · January 2017 There is a paucity of information concerning the developmental neurotoxicity (DNT) hazard posed by industrial and environmental chemicals. New testing approaches will most likely be based on batteries of alternative and complementary (non-animal) tests. As ... Full text Cite

Using zebrafish to assess developmental neurotoxicity

Chapter · January 1, 2017 It is widely accepted that the developing nervous system is especially vulnerable to a variety of chemicals, including drugs and environmental contaminants. It is also clear that our understanding of the risks from chemical exposures during development is ... Full text Cite

Development of a quantitative morphological assessment of toxicant-treated zebrafish larvae using brightfield imaging and high-content analysis.

Journal Article Journal of applied toxicology : JAT · September 2016 One of the rate-limiting procedures in a developmental zebrafish screen is the morphological assessment of each larva. Most researchers opt for a time-consuming, structured visual assessment by trained human observer(s). The present studies were designed t ... Full text Cite

Esterase detoxication of acetylcholinesterase inhibitors using human liver samples in vitro.

Journal Article Toxicology · April 2016 Organophosphorus (OP) and N-methylcarbamate pesticides inhibit acetylcholinesterase (AChE), but differences in metabolism and detoxication can influence potency of these pesticides across and within species. Carboxylesterase (CaE) and A-esterase (paraoxona ... Full text Cite

Advancing toxicology research using in vivo high throughput toxicology with small fish models.

Journal Article ALTEX · January 2016 Small freshwater fish models, especially zebrafish, offer advantages over traditional rodent models, including low maintenance and husbandry costs, high fecundity, genetic diversity, physiology similar to that of traditional biomedical models, and reduced ... Full text Cite

Fetal Origins of Life Stage Disease: A Zebrafish Model for the Obesity Epidemic.

Conference ENVIRONMENTAL AND MOLECULAR MUTAGENESIS · 2016 Cite

Expanding the test set: Chemicals with potential to disrupt mammalian brain development.

Journal Article Neurotoxicology and teratology · November 2015 High-throughput test methods including molecular, cellular, and alternative species-based assays that examine critical events of normal brain development are being developed for detection of developmental neurotoxicants. As new assays are developed, a "tra ... Full text Cite

Use of alternative assays to identify and prioritize organophosphorus flame retardants for potential developmental and neurotoxicity.

Journal Article Neurotoxicology and teratology · November 2015 Due to their toxicity and persistence in the environment, brominated flame retardants (BFRs) are being phased out of commercial use, leading to the increased use of alternative chemicals such as the organophosphorus flame retardants (OPFRs). There is, howe ... Full text Cite

Acute and developmental behavioral effects of flame retardants and related chemicals in zebrafish.

Journal Article Neurotoxicology and teratology · November 2015 As polybrominated diphenyl ethers are phased out, numerous compounds are emerging as potential replacement flame retardants for use in consumer and electronic products. Little is known, however, about the neurobehavioral toxicity of these replacements. Thi ... Full text Cite

Can zebrafish be used to identify developmentally neurotoxic chemicals?

Conference Neurotoxicology and Teratology · May 2015 Full text Cite

Developmental exposure to organophosphate flame retardants elicits overt toxicity and alters behavior in early life stage zebrafish (Danio rerio).

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · December 2014 Organophosphate flame retardants (OPFRs) are common replacements for the phased-out polybrominated diphenyl ethers (PBDEs) and have been detected at high concentrations in environmental samples. OPFRs are structurally similar to organophosphate pesticides ... Full text Cite

Immediate and long-term consequences of vascular toxicity during zebrafish development.

Journal Article Reproductive toxicology (Elmsford, N.Y.) · September 2014 Proper formation of the vascular system is necessary for embryogenesis, and chemical disruption of vascular development may be a key event driving developmental toxicity. In order to test the effect of environmental chemicals on this critical process, we e ... Full text Cite

Biomarkers of toxicity in zebrafish

Chapter · January 1, 2014 Given that zebrafish have now become an accepted model for toxicological studies in both the human health and ecological communities, this chapter takes stock of the status of biomarkers of toxicity that have been proposed for the zebrafish model. Most of ... Full text Cite

Zebrafish Development: High-Throughput Test Systems to Assess Developmental Toxicity

Chapter · March 4, 2013 Because of its developmental concordance, ease of handling and rapid development, the small teleost, zebrafish (Danio rerio), is frequently promoted as a vertebrate model for medium-throughput developmental screens. This present chapter discusses zebrafish ... Full text Cite

Acute administration of dopaminergic drugs has differential effects on locomotion in larval zebrafish.

Journal Article Pharmacology, biochemistry, and behavior · February 2013 Altered dopaminergic signaling causes behavioral changes in mammals. In general, dopaminergic receptor agonists increase locomotor activity, while antagonists decrease locomotor activity. In order to determine if zebrafish (a model organism becoming popula ... Full text Cite

Impact of chemical proportions on the acute neurotoxicity of a mixture of seven carbamates in preweanling and adult rats.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · September 2012 Statistical design and environmental relevance are important aspects of studies of chemical mixtures, such as pesticides. We used a dose-additivity model to test experimentally the default assumptions of dose additivity for two mixtures of seven N-methylca ... Full text Cite

Update on EPA's ToxCast program: providing high throughput decision support tools for chemical risk management.

Journal Article Chemical research in toxicology · July 2012 The field of toxicology is on the cusp of a major transformation in how the safety and hazard of chemicals are evaluated for potential effects on human health and the environment. Brought on by the recognition of the limitations of the current paradigm in ... Full text Cite

Zebrafish developmental screening of the ToxCast™ Phase I chemical library.

Journal Article Reproductive toxicology (Elmsford, N.Y.) · April 2012 Zebrafish (Danio rerio) is an emerging toxicity screening model for both human health and ecology. As part of the Computational Toxicology Research Program of the U.S. EPA, the toxicity of the 309 ToxCast™ Phase I chemicals was assessed using a zebrafish s ... Full text Cite

Developmental exposure to valproate and ethanol alters locomotor activity and retino-tectal projection area in zebrafish embryos.

Journal Article Reproductive toxicology (Elmsford, N.Y.) · April 2012 Given the minimal developmental neurotoxicity data available for the large number of new and existing chemicals, there is a critical need for alternative methods to identify and prioritize chemicals for further testing. We outline a developmental neurotoxi ... Full text Cite

Assessing locomotor activity in larval zebrafish: Influence of extrinsic and intrinsic variables.

Journal Article Neurotoxicology and teratology · November 2011 The U.S. Environmental Protection Agency is evaluating methods to screen and prioritize large numbers of chemicals for developmental toxicity. We are exploring methods to detect developmentally neurotoxic chemicals using zebrafish behavior at 6 days of age ... Full text Cite

Rearing conditions differentially affect the locomotor behavior of larval zebrafish, but not their response to valproate-induced developmental neurotoxicity.

Journal Article Neurotoxicology and teratology · November 2011 Zebrafish (Danio rerio) are widely used in developmental research, but still not much is known about the role of the environment in their development. Zebrafish are a highly social organism; thus exposure to, or isolation from, social environments may have ... Full text Cite

Adverse outcome pathways during early fish development: a conceptual framework for identification of chemical screening and prioritization strategies.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · October 2011 The fish early life-stage (FELS) test guideline (OECD 210 or OCSPP 850.1400) is the most frequently used bioassay for predicting chronic fish toxicity and supporting aquatic ecological risk assessments around the world. For each chemical, the FELS test req ... Full text Cite

Zebrafish: as an integrative model for twenty-first century toxicity testing.

Journal Article Birth defects research. Part C, Embryo today : reviews · September 2011 The zebrafish embryo is a useful small model for investigating vertebrate development because of its transparency, low cost, transgenic and morpholino capabilities, conservation of cell signaling, and concordance with mammalian developmental phenotypes. Fr ... Full text Cite

Generation and characterization of neurogenin1-GFP transgenic medaka with potential for rapid developmental neurotoxicity screening.

Journal Article Aquatic toxicology (Amsterdam, Netherlands) · September 2011 Fish models such as zebrafish and medaka are increasingly used as alternatives to rodents in developmental and toxicological studies. These developmental and toxicological studies can be facilitated by the use of transgenic reporters that permit the real-t ... Full text Cite

The zebrafish embryo model in toxicology and teratology, September 2–3, 2010, Karlsruhe, Germany.

Conference Reproductive toxicology (Elmsford, N.Y.) · May 2011 The use of fish embryos is gaining popularity for research in the area of toxicology and teratology. Particularly embryos of the zebrafish offer an array of different applications ranging from regulatory testing to mechanistic research. For this reason a c ... Full text Cite

Esterase metabolism of cholinesterase inhibitors using rat liver in vitro.

Journal Article Toxicology · March 2011 A variety of chemicals, such as organophosphate (OP) and carbamate pesticides, nerve agents, and industrial chemicals, inhibit acetylcholinesterase (AChE) leading to overstimulation of the cholinergic nervous system. The resultant neurotoxicity is similar ... Full text Cite

Using zebrafish to assess developmental neurotoxicity

Chapter · January 1, 2011 This chapter discusses zebrafish to assess developmental neurotoxicity. Zebrafish have become a popular test species in toxicology, pharmacology and biomedical research. This chapter addresses several issues, results and research needs regarding the use of ... Full text Cite

Predictive Modeling of Developmental Toxicity

Conference BIRTH DEFECTS RESEARCH PART A-CLINICAL AND MOLECULAR TERATOLOGY · 2011 Cite

Silver nanoparticles alter zebrafish development and larval behavior: distinct roles for particle size, coating and composition.

Journal Article Neurotoxicol Teratol · 2011 Silver nanoparticles (AgNPs) act as antibacterials by releasing monovalent silver (Ag(+)) and are increasingly used in consumer products, thus elevating exposures in human and wildlife populations. In vitro models indicate that AgNPs are likely to be devel ... Full text Link to item Cite

Evaluation of candidate genes for cholinesterase activity in farmworkers exposed to organophosphorus pesticides: association of single nucleotide polymorphisms in BCHE.

Journal Article Environmental health perspectives · October 2010 BackgroundOrganophosphate pesticides act as cholinesterase inhibitors. For those with agricultural exposure to these chemicals, risk of potential exposure-related health effects may be modified by genetic variability in cholinesterase metabolism. ... Full text Cite

Relationship between brain and plasma carbaryl levels and cholinesterase inhibition.

Journal Article Toxicology · October 2010 Carbaryl is a N-methylcarbamate pesticide and, like others in this class, is a reversible inhibitor of cholinesterase (ChE) enzymes. Although studied for many years, there is a surprising lack of information relating tissue levels of carbaryl with ChE acti ... Full text Cite

The dynamics of successive induction in larval zebrafish.

Journal Article Journal of the experimental analysis of behavior · September 2010 Charles Sherrington identified the properties of the synapse by purely behavioral means-the study of reflexes-more than 100 years ago. They were subsequently confirmed neurophysiologically. Studying reflex interaction, he also showed that activating one re ... Full text Open Access Cite

Gene expression changes in developing zebrafish as potential markers for rapid developmental neurotoxicity screening.

Journal Article Neurotoxicology and teratology · January 2010 Hazard information essential to guide developmental neurotoxicity risk assessments is limited for many chemicals. As developmental neurotoxicity testing using rodents is laborious and expensive, alternative species such as zebrafish are being adapted for r ... Full text Cite

Acute neuroactive drug exposures alter locomotor activity in larval zebrafish.

Journal Article Neurotoxicology and teratology · January 2010 As part of the development of a rapid in vivo screen for prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae by assessing the acute effects of prototypic drugs that act on the central ne ... Full text Cite

Use of medaka in toxicity testing.

Journal Article Current protocols in toxicology · February 2009 Small aquarium fishes are increasingly used as animal models, and one of these, the Japanese Medaka (Oryzias latipes), is frequently utilized for toxicity testing. While these vertebrates have many similarities with their terrestrial counterparts, there ar ... Full text Cite

Locomotion in larval zebrafish: Influence of time of day, lighting and ethanol.

Journal Article Neurotoxicology · January 2009 The increasing use of zebrafish (Danio rerio) in developmental research highlights the need for a detailed understanding of their behavior. We studied the locomotion of individual zebrafish larva (6 days post-fertilization) in 96-well microtiter plates. Mo ... Full text Cite

Toxic responses of the fish nervous system

Chapter · January 1, 2008 Few of the approximately 70,000 chemicals on the Toxic Substances Control Act inventory or the 1000 to 1600 new chemicals introduced each year in the United States have been tested for neurotoxicity to support risk assessments (NRC, 1992), even though it i ... Full text Cite

Comparison of acute neurobehavioral and cholinesterase inhibitory effects of N-methylcarbamates in rat.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · August 2007 While the cholinesterase-inhibiting N-methyl carbamate pesticides have been widely used, there are few studies evaluating direct functional and biochemical consequences of exposure. In the present study of the acute toxicity of seven N-methyl carbamate pes ... Full text Cite

Letter to the editor [3]

Journal Article Toxicological Sciences · August 1, 2007 Full text Cite

Re: age-related brain cholinesterase inhibition kinetics following in vitro incubation with chlorpyrifos-oxon and diazinon-oxon.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · August 2007 Full text Cite

Time course of cholinesterase inhibition in adult rats treated acutely with carbaryl, carbofuran, formetanate, methomyl, methiocarb, oxamyl or propoxur.

Journal Article Toxicology and applied pharmacology · March 2007 To compare the toxicity of seven N-methyl carbamates, time course profiles for brain and red blood cell (RBC) cholinesterase (ChE) inhibition were established for each. Adult, male, Long Evans rats (n=4-5 dose group) were dosed orally with either carbaryl ... Full text Cite

Cumulative effects of organophosphorus or carbamate pesticides*

Chapter · December 1, 2006 The chapter is designed to address issues of experiment design of mixture studies; summarize the available literature on organophosphate (OP) pesticide mixtures, carbamate (CM) pesticide mixtures, and mixtures of OP and CM pesticides; and address future re ... Full text Cite

Vulnerable windows for developmental ethanol toxicity in the Japanese medaka fish (Oryzias latipes).

Journal Article Aquatic toxicology (Amsterdam, Netherlands) · December 2006 Ethanol (EtOH) is a well-known developmental toxicant that produces a range of abnormal phenotypes in mammalian systems including craniofacial abnormalities, cognitive deficits and growth retardation. While the toxic potential of developmental EtOH exposur ... Full text Cite

Measuring cholinesterase activity in human saliva.

Journal Article Journal of toxicology and environmental health. Part A · October 2006 To assess the potential for using saliva in pesticide biomonitoring, the consistency of cholinesterase activity in human saliva collected over time was examined. In this pilot study, saliva was collected from 20 healthy adults once per week for 5 consecuti ... Full text Cite

Adapting the medaka embryo assay to a high-throughput approach for developmental toxicity testing.

Journal Article Neurotoxicology · September 2006 Chemical exposure during embryonic development may cause persistent effects, yet developmental toxicity data exist for very few chemicals. Current testing procedures are time consuming and costly, underlining the need for rapid and low cost screening strat ... Full text Cite

Characterization of deltamethrin metabolism by rat plasma and liver microsomes.

Journal Article Toxicology and applied pharmacology · April 2006 Deltamethrin, a widely used type II pyrethroid insecticide, is a relatively potent neurotoxicant. While the toxicity has been extensively examined, toxicokinetic studies of deltamethrin and most other pyrethroids are very limited. The aims of this study we ... Full text Cite

Ontogeny of hepatic and plasma metabolism of deltamethrin in vitro: role in age-dependent acute neurotoxicity.

Journal Article Drug metabolism and disposition: the biological fate of chemicals · March 2006 Deltamethrin (DLM) is a relatively potent and widely used pyrethroid insecticide. Inefficient detoxification has been proposed to be the primary reason for the greater sensitivity of immature rats to the acute neurotoxicity of DLM. The objective of this st ... Full text Cite

A tiered approach to systemic toxicity testing for agricultural chemical safety assessment.

Journal Article Critical reviews in toxicology · January 2006 A proposal has been developed by the Agricultural Chemical Safety Assessment (ACSA) Technical Committee of the ILSI Health and Environmental Sciences Institute (HESI) for an improved approach to assessing the safety of crop protection chemicals. The goal i ... Full text Cite

Cumulative Effects of Organophosphorus or Carbamate Pesticides

Chapter · December 13, 2005 The chapter is designed to address issues of experiment design of mixture studies; summarize the available literature on organophosphate (OP) pesticide mixtures, carbamate (CM) pesticide mixtures, and mixtures of OP and CM pesticides; and address future re ... Full text Cite

Neurochemical effects of chronic dietary and repeated high-level acute exposure to chlorpyrifos in rats.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · November 2005 Very little is known about the effects of chronic exposure to relatively low levels of anticholinesterase insecticides or how the effects of chronic exposure compare to those of higher, intermittent exposure. To that end, adult male rats were fed an antich ... Full text Cite

Neurobehavioral effects of chronic dietary and repeated high-level spike exposure to chlorpyrifos in rats.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · August 2005 This study aimed to model long-term subtoxic human exposure to an organophosphorus pesticide, chlorpyrifos, and to examine the influence of that exposure on the response to intermittent high-dose acute challenges. Adult Long-Evans male rats were maintained ... Full text Cite

Carbamate pesticides

Chapter · January 1, 2005 Full text Cite

Further assessment of an in vitro screen that may help identify organophosphorus pesticides that are more acutely toxic to the young.

Journal Article Journal of toxicology and environmental health. Part A · September 2004 Some, but not all, organophosphorus pesticides are more acutely toxic to the young as compared to adults. We have developed an in vitro assay that measures the detoxification potential (via carboxylesterase and A-esterases) of tissues. Previous results usi ... Full text Cite

A dried blood spot method to evaluate cholinesterase activity in young children.

Journal Article Archives of environmental health · September 2004 Field methods are needed to detect and monitor the organophosphate pesticide exposure of young children. Twenty children, aged 11 to 18 mo, living in an agricultural community along the United States/Mexico border were enrolled in a pilot study investigati ... Full text Cite

Automated measurement of acetylcholinesterase activity in rat peripheral tissues.

Journal Article Toxicology · April 2003 The accepted mechanism of toxicity of many organophosphorous and carbamate insecticides is inhibition of acetylcholinesterase activity. In mammals, part of the toxicity assessment usually includes monitoring blood and/or brain acetylcholinesterase inhibiti ... Full text Cite

Developmental neurotoxicity of chlorpyrifos: what is the vulnerable period?

Journal Article Environ Health Perspect · November 2002 Previously, we found that exposure of neonatal rats to chlorpyrifos (CPF) produced brain cell damage and loss, with resultant abnormalities of synaptic development. We used the same biomarkers to examine prenatal CPF treatment so as to define the critical ... Full text Link to item Cite

Tissue carboxylesterases and chlorpyrifos toxicity in the developing rat

Journal Article Human and Ecological Risk Assessment · January 1, 2002 Young animals are more sensitive than adults to the neurotoxic effects of some organophosphorus insecticides. Many investigators attribute this difference in sensitivity to the immaturity of the detoxification capacity of preweanling rats. Chlorpyrifos [O, ... Full text Cite

An invertebrate model of the developmental neurotoxicity of insecticides: effects of chlorpyrifos and dieldrin in sea urchin embryos and larvae.

Journal Article Environ Health Perspect · July 2001 Chlorpyrifos targets mammalian brain development through a combination of effects directed at cholinergic receptors and intracellular signaling cascades that are involved in cell differentiation. We used sea urchin embryos as an invertebrate model system t ... Full text Link to item Cite

Methods to identify and characterize developmental neurotoxicity for human health risk assessment. III: pharmacokinetic and pharmacodynamic considerations.

Journal Article Environmental health perspectives · March 2001 We review pharmacokinetic and pharmacodynamic factors that should be considered in the design and interpretation of developmental neurotoxicity studies. Toxicologic effects on the developing nervous system depend on the delivered dose, exposure duration, a ... Full text Cite

Biochemical approaches to studying neurotoxicity.

Journal Article Current protocols in toxicology · January 2001 This overview provides an introduction to biochemical analysis of toxicant effects on the nervous system. It includes a brief discussion of the salient features of the nervous system and a review of the various approaches used to detect and identify neurot ... Full text Cite

Comparison of the role of esterases in the differential age-related sensitivity to chlorpyrifos and methamidophos.

Journal Article Neurotoxicology · February 2000 More than 30 years ago, scientists recognized that, at a given dosage, the young rat was more sensitive than the adult to the toxicity of many organophosphorus, anticholinesterase pesticides. This observation went basically unexamined until recently. Renew ... Cite

Gestational exposure to chlorpyrifos: dose response profiles for cholinesterase and carboxylesterase activity.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · November 1999 This study investigates the in vivo dose response profiles of the target enzyme cholinesterase (ChE) and the detoxifying enzymes carboxylesterase (CaE) in the fetal and maternal compartments of pregnant rats dosed with chlorpyrifos [(O,O'-diethyl O-3,5,6-t ... Full text Cite

Influence of storage conditions on the stability of cholinesterase activity in plasma and brain tissue taken from carbamate or organophosphorus pesticide-treated rats

Journal Article Toxicology Methods · July 1, 1999 Cholinesterase (ChE) activity in tissues from carbamate-treated animals is especially difficult to analyze because the inhibited ChE tends to decarbamylate, leading to an underestimation of ChE inhibition. Given this instability during analysis, reactivati ... Full text Cite

Gestational exposure to chlorpyrifos: comparative distribution of trichloropyridinol in the fetus and dam.

Journal Article Toxicology and applied pharmacology · July 1999 Chlorpyrifos (O,O'-diethyl O-[3,5,6-trichloro-2-pyridyl] phosphorothionate) is a commonly used anticholinesterase insecticide, and therefore the potential for human exposure is high. The present time course and dose response studies were conducted to delin ... Full text Cite

Age- and gender-related differences in sensitivity to chlorpyrifos in the rat reflect developmental profiles of esterase activities.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · December 1998 Young rats are more sensitive than adults to a single oral dose of chlorpyrifos, an organophosphorus pesticide. A direct comparison of chlorpyrifos effects in young (postnatal day 17; PND17), adolescent (PND27), and adult (70 days) Long-Evans rats was cond ... Full text Cite

Gestational exposure to chlorpyrifos: apparent protection of the fetus?

Journal Article Toxicology and applied pharmacology · September 1998 Previous studies have shown that, in general, young, postnatal animals are more sensitive than adults to the toxic effects of anticholinesterase (antiChE) pesticides. Paradoxically, often fetal brain cholinesterase (ChE) is less inhibited than maternal bra ... Full text Cite

Age- and gender-related differences in the time course of behavioral and biochemical effects produced by oral chlorpyrifos in rats.

Journal Article Toxicology and applied pharmacology · March 1998 It is well known that young animals are generally more sensitive to lethal effects of cholinesterase-inhibiting pesticides, but there are sparse data comparing less-than-lethal effects. We compared the behavioral and biochemical toxicity of chlorpyrifos in ... Full text Cite

Common mechanism of toxicity: a case study of organophosphorus pesticides.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · January 1998 The Food Quality Protection Act of 1996 (FQPA) requires the EPA to consider "available information concerning the cumulative effects of such residues and other substances that have a common mechanism of toxicity ... in establishing, modifying, leaving in e ... Full text Cite

Comparison of the in vitro sensitivity of rat acetylcholinesterase to chlorpyrifos-oxon: what do tissue IC50 values represent?

Journal Article Toxicology and applied pharmacology · January 1998 The toxicological literature is replete with studies which have attempted to correlate differences in in vivo sensitivity to anticholinesterases with a common in vitro measure: acetylcholinesterase (AChE) IC50 values. Generally, it is assumed that these IC ... Full text Cite

Rat brain acetylcholinesterase activity: developmental profile and maturational sensitivity to carbamate and organophosphorus inhibitors.

Journal Article Toxicology · January 1998 A growing body of evidence indicates that young animals exhibit an increased susceptibility to the lethal effects of cholinesterase (ChE)-inhibiting insecticides. Our laboratory is engaged in defining factors which may explain this age-related sensitivity. ... Full text Cite

Ontogenetic differences in the regional and cellular acetylcholinesterase and butyrylcholinesterase activity in the rat brain.

Journal Article Brain research. Developmental brain research · January 1998 Considering the novel functions for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the developing nervous system (reviewed in Layer and Willbold, Prog. Histochem. Cytochem., 1995) a quantitative survey of the spatiotemporal developme ... Full text Cite

Ontogenetic differences in the regional and cellular acetylcholinesterase and butyrylcholinesterase activity in the rat brain

Journal Article Brain research. Developmental brain research · January 1998 Considering the novel functions for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the developing nervous system (reviewed in Layer and Willbold, Prog. Histochem. Cytochem., 1995) a quantitative survey of the spatiotemporal developme ... Full text Cite

The relationship of oral chlorpyrifos effects on behavior, cholinesterase inhibition, and muscarinic receptor density in rat.

Journal Article Pharmacology, biochemistry, and behavior · September 1997 Behavioral changes and tissue cholinesterase (ChE) inhibition were examined in animals treated with the commonly used insecticide chlorpyrifos. Adult male rats were dosed by gavage with 0, 10, 30, 60, or 100 mg/kg chlorpyrifos. Rats (n = 20/dose group) wer ... Full text Cite

Tissue-specific effects of chlorpyrifos on carboxylesterase and cholinesterase activity in adult rats: an in vitro and in vivo comparison.

Journal Article Fundamental and applied toxicology : official journal of the Society of Toxicology · August 1997 Organophosphate (OP) pesticides can bind to carboxylesterase (CaE), which may lower the concentration of OPs at the target site enzyme, acetylcholinesterase (ChE). It is unclear from the literature whether it is the CaE's affinity for the OP and/or the num ... Full text Cite

Cellular mechanisms for developmental toxicity of chlorpyrifos: targeting the adenylyl cyclase signaling cascade.

Journal Article Toxicol Appl Pharmacol · July 1997 Developmental neurotoxicity caused by chlorpyrifos exposure is generally thought to target cholinesterase but chlorpyrifos may also act on cellular intermediates, such as adenylyl cyclase, that serve global functions in the coordination of cell development ... Full text Link to item Cite

Automated Instrument Analysis of Cholinesterase Activity in Tissues from Carbamate-Treated Animals: A Cautionary Note

Journal Article Toxicology Methods · January 1, 1997 When using a spectrophotometric method to measure cholinesterase activity in carbamate-treated tissues, precautions must be taken to limit the reactivation of the inhibited cholinesterase. Many testing laboratories use automated instruments to measure chol ... Full text Cite

Quantitative, video-based histochemistry to measure regional effects of anticholinesterase pesticides in rat brain.

Journal Article Analytical biochemistry · October 1996 Acetylcholinesterase histochemistry was coupled to inexpensive and widely available apparatus for video microscopy and densitometry to study enzyme activity and inhibition in different parts of the rat brain. Quantitative histochemistry, under properly def ... Full text Cite

Validation of the use of 6,6'-dithiodinicotinic acid as a chromogen in the Ellman method for cholinesterase determinations.

Journal Article Veterinary and human toxicology · August 1996 The Ellman method for cholinesterase determination is a spectrophotometric method which entails the use of 5,5'-dithiobis-(2-nitrobenzoic) acid (DTNB) as a chromogen and records the level of cholinesterase activity as the change in absorbance at 412 nm. Al ... Cite

The impact of dose rate on the neurotoxicity of acrylamide: the interaction of administered dose, target tissue concentrations, tissue damage, and functional effects.

Journal Article Toxicology and applied pharmacology · July 1996 Health agencies are often required to predict the effects of long term low level exposure in humans based on annual data involving short-term high-level exposures. Uncertainties in extrapolation can be, in part, based on potentially different mechanism ass ... Full text Cite

Factors in standardizing automated cholinesterase assays.

Journal Article Journal of toxicology and environmental health · June 1996 A scientific panel assembled by the U.S. Environmental Protection Agency (EPA) determined that variability in cholinesterase (ChE) activities in the agency's pesticide/animal study database likely was due to a lack of accepted guidelines for ChE methodolog ... Full text Cite

Inhibition of rat brain phosphatidylinositol-specific phospholipase C by aluminum: regional differences, interactions with aluminum salts, and mechanisms.

Journal Article Toxicology and applied pharmacology · January 1996 We have shown previously that aluminum chloride (AlCl3, 10-500 microM) inhibits hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) by phosphatidylinositol-specific phospholipase C (PI-PLC) in a concentration-dependent manner. In the present study, ... Full text Cite

Maturational differences in chlorpyrifos-oxonase activity may contribute to age-related sensitivity to chlorpyrifos.

Journal Article Journal of biochemical toxicology · January 1996 Chlorpyrifos (CPF), a commonly used cholinesterase-inhibiting insecticide, is lethal at much lower doses to young animals than adults. To explain this higher sensitivity in younger animals, we hypothesized that young rats have less chlorpyrifos-oxonase (CP ... Full text Cite

Factors in standardizing automated cholinesterase assays (vol 48, pg 187, 1996)

Journal Article JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH · 1996 Cite

Blood cholinesterase activity: Inhibition as an indicator of adverse effect

Journal Article BIOMARKERS FOR AGROCHEMICALS AND TOXIC SUBSTANCES · 1996 Cite

Regulatory and research issues related to cholinesterase inhibition.

Journal Article Toxicology · September 1995 Assessing the neurotoxic potential of organophosphate and carbamate pesticides should be greatly facilitated by the knowledge that the mechanism of action of these insecticides is presumed to be the inhibition of cholinesterase, the enzyme which controls t ... Full text Cite

Slow accumulation of acetylcholinesterase in rat brain during enzyme inhibition by repeated dosing with chlorpyrifos.

Journal Article Biochemical pharmacology · March 1995 When given to rats, O,O'-diethyl-O-[3,5,6-trichloro-2-pyridyl]- phosphorothionate (chlorpyrifos), a common insecticide, causes an unusually lengthy dose-dependent fall in the activity of brain acetylcholinesterase (AChE; EC 3.1.1.7). To determine whether t ... Full text Cite

Comparison of the relative inhibition of acetylcholinesterase and neuropathy target esterase in rats and hens given cholinesterase inhibitors.

Journal Article Fundamental and applied toxicology : official journal of the Society of Toxicology · January 1995 Inhibition of neuropathy target esterase (NTE, neurotoxic esterase) and acetylcholinesterase (AChE) activities was compared in brain and spinal cords of adult While Leghorn hens and adult male Long Evan rats 4-48 hr after administration of triortho-tolyl p ... Full text Cite

A novel method that markedly increases the sensitivity of the erythrocyte acetylcholinesterase assay, suitable for use in pesticide-treated rats

Journal Article Toxicology Mechanisms and Methods · January 1, 1995 Although the specific activity of rat erythrocyte acetylcholinesterase activity is reasonably high, use of the standard spectrophotometric assay presents special problems due primarily to the interference of hemoglobin with the absorbance spectrum of the a ... Full text Cite

The neurotoxicity of cholinesterase-inhibiting insecticides: Past and present evidence demonstrating persistent effects

Journal Article Inhalation Toxicology · January 1, 1995 It is assumed that the primary mechanism of action of carbamate and organophosphate insecticides is the inhibition of an enzyme, acetylcholinesterase (AChE; EC 3.1.1.7). This enzyme normally maintains the proper level of the neurotransmitter acetylcholine ... Full text Cite

Clinical blood cholinesterase measurements for monitoring pesticide exposures

Conference ENZYMES OF THE CHOLINESTERASE FAMILY · 1995 Cite

BLOOD CHOLINESTERASE ACTIVITY - CAN INHIBITION DE INDICATIVE OF ADVERSE EFFECT AS WELL AS EXPOSURE

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · 1995 Cite

Studies on the correlation between blood cholinesterase inhibition and 'target tissue' inhibition in pesticide-treated rats.

Journal Article Toxicology · September 1994 Inhibition of cholinesterase activity in the blood has been proposed as an index of ChE activity in tissues targeted by ChE-inhibiting pesticides, including the muscle end-plate region and the central nervous system (CNS). While opinions vary regarding the ... Full text Cite

Fenthion produces a persistent decrease in muscarinic receptor function in the adult rat retina.

Journal Article Toxicology and applied pharmacology · April 1994 Several reports have suggested that exposure to organophosphate pesticides damages the visual system. The prolonged effects of an acute dose of fenthion (dimethyl 3-methyl-4-methylthiophenyl phosphorothionate) were studied on the cholinergic system of the ... Full text Cite

Effects of organophosphates on the visual system of rats.

Journal Article Journal of applied toxicology : JAT · March 1994 The possibility that exposure to organophosphate insecticides can lead to ocular damage is suggested by Japanese studies from the 1960s and 1970s indicating that exposed humans developed chronic ocular degeneration, in addition to showing more commonly acc ... Full text Cite

CHLORPYRIFOS INCREASES BRAIN ACETYLCHOLINESTERASE

Conference JOURNAL OF NEUROCHEMISTRY · 1994 Cite

LEAD (PB) PERTURBS RETINAL MUSCARINIC RECEPTOR FUNCTION

Conference JOURNAL OF NEUROCHEMISTRY · 1994 Cite

Determination of acrylamide in rat serum and sciatic nerve by gas chromatography-electron-capture detection.

Journal Article Journal of chromatography · September 1993 A modified method for the derivatization and determination of acrylamide as 2-bromopropenamide by gas chromatography-electron-capture detection was developed and applied to serum and sciatic nerve from rats. The method was accurate and precise over the cal ... Full text Cite

A modified spectrophotometric method appropriate for measuring cholinesterase activity in tissue from carbaryl-treated animals.

Journal Article Fundamental and applied toxicology : official journal of the Society of Toxicology · August 1993 Inhibited cholinesterase in tissues of animals exposed to carbamate pesticides is known to reactivate readily, presenting considerable problems in the accurate assessment of cholinesterase activity in these tissues. Decarbamylation of cholinesterase is fav ... Full text Cite

Direct measurement of fast axonal organelle transport in the sciatic nerve of rats treated with acrylamide.

Journal Article Journal of toxicology and environmental health · August 1993 The effects of acrylamide on fast axonal transport have been measured primarily using the indirect methods of isotope or enzyme accumulation. We report the first direct evaluation of the effects of subchronic acrylamide dosing (150, 300, or 500 mg/kg total ... Full text Cite

Behavioral and neurochemical effects of acute chlorpyrifos in rats: tolerance to prolonged inhibition of cholinesterase.

Journal Article The Journal of pharmacology and experimental therapeutics · August 1993 The preponderance of studies of tolerance to organophosphate (OP) cholinesterase (ChE) inhibitors indicates that functional recovery accompanies neurochemical compensations for the inhibited enzyme. Contrary to prediction, rats dosed with the OP diisopropy ... Cite

Relationship of neuropathy target esterase inhibition to neuropathology and ataxia in hens given organophosphorus esters.

Journal Article Chemico-biological interactions · June 1993 Adult White Leghorn hens were acutely exposed to 3 dosages of the following organophosphorus compounds: mipafox, tri-ortho-tolyl phosphate (TOTP), phenyl saligenin phosphate, and diisopropylphosphorofluoridate (DFP). Neuropathy target esterase (NTE) activi ... Full text Cite

The role of neurotoxic esterase (NTE) in the prevention and potentiation of organophosphorus-induced delayed neurotoxicity (OPIDN).

Journal Article Chemico-biological interactions · June 1993 The first step in the initiation of organophosphorus-induced delayed neuropathy (OPIDN) is proposed to be the phosphorylation of an enzyme found in the nervous system called neurotoxic esterase (neuropathy target esterase, NTE). It has been known for over ... Full text Cite

Locally synthesized phosphatidylcholine, but not protein, undergoes rapid retrograde axonal transport in the rat sciatic nerve.

Journal Article Journal of neurochemistry · May 1993 Retrograde axonal transport of phosphatidylcholine in the sciatic nerve has been demonstrated only after injection of lipid precursors into the cell body region. We now report, however, that after microinjection (1 microliter) of [methyl-3H]choline chlorid ... Full text Cite

Developmental changes in carbachol-stimulated inositolphosphate release in pigmented rat retina.

Journal Article Current eye research · May 1993 Carbachol-stimulated release of inositolphosphates (IP) was studied in the whole retina from Long-Evans rats of different ages (day 5, 10, 15, 20, adult) following in vitro incorporation of [3H]myo-inositol. Unlike the albino rat retina, the pigmented reti ... Full text Cite

Paraoxon toxicity is not potentiated by prior reduction in blood acetylcholinesterase.

Journal Article Toxicology and applied pharmacology · November 1992 The role of blood acetylcholinesterase in moderating the effects of organophosphate challenge in rats was tested. Adult male rats (n = 42) were injected (iv) either with monoclonal antibodies (MAb) to rat acetylcholinesterase (EC 3.1.1.7; AChE) or normal m ... Full text Cite

Subacute ethanol consumption reverses p-xylene-induced decreases in axonal transport.

Journal Article Toxicology · November 1992 Human exposure to organic solvents is often complicated by ethanol ingestion and the literature is replete with demonstrations of metabolic interactions between ethanol and organic solvents at a pharmacokinetic level. Because of the possible modulation of ... Full text Cite

Altered expression of pp60c-src induced by peripheral nerve injury.

Journal Article The Journal of comparative neurology · January 1992 The normal src protein (pp60c-src) is localized principally in the nerve growth cone of developing neurons and declines to low levels with synaptic maturation. To determine whether pp60c-src is reexpressed in regenerating axons, its expression was studied ... Full text Cite

Phenylmethylsulfonyl fluoride alters sensitivity to organophosphorus-induced delayed neurotoxicity in developing animals.

Journal Article Neurotoxicology · January 1992 The serine/cysteine hydrolase inhibitor phenylmethylsulfonyl fluoride (PMSF) markedly intensifies the clinical expression of organophosphorus-induced delayed neurotoxicity (OPIDN) in adult chickens when administered after organophosphate exposure. In this ... Cite

Retrograde axonal transport of locally synthesized phosphoinositides in the rat sciatic nerve.

Journal Article Journal of neurochemistry · August 1991 Although autoradiography has demonstrated local incorporation of [3H]inositol into axonal phospholipids after intraneural injection, retrograde axonal transport of phosphatidylinositol has only been demonstrated after injection of lipid precursor into the ... Full text Cite

Murine susceptibility to organophosphorus-induced delayed neuropathy (OPIDN).

Journal Article Toxicology and applied pharmacology · February 1991 This study reports that CD-1 strain mice are neuropathologically and biochemically responsive to acute doses of tri-ortho-cresyl phosphate (TOCP). Young (25-30 g) male and female animals were exposed (po) to a single dose of TOCP (580-3480 mg/kg) and sampl ... Full text Cite

Behavioral and neurochemical changes in rats dosed repeatedly with diisopropylfluorophosphate.

Journal Article The Journal of pharmacology and experimental therapeutics · February 1991 Behavioral effects of organophosphates (OPs) typically decrease with repeated exposure, despite persistence of OP-induced inhibition of acetylcholinesterase (AChE) and downregulation of muscarinic acetylcholine (ACh) receptors. To characterize this toleran ... Cite

Potentiation of organophosphorus-induced delayed neurotoxicity by phenylmethylsulfonyl fluoride.

Journal Article Journal of toxicology and environmental health · December 1990 It is well known that pretreatment with the serine esterase inhibitor phenylmethylsulfonyl fluoride (PMSF) can protect experimental animals from organophosphorus-induced delayed neurotoxicity (OPIDN), presumably by blocking the active site of neurotoxic es ... Full text Cite

RODENT SUSCEPTIBILITY TO ORGANOPHOSPHATE-INDUCED DELAYED NEUROPATHY (OPIDN)

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · 1990 Cite

Effects of p-xylene inhalation on axonal transport in the rat retinal ganglion cells.

Journal Article Toxicology and applied pharmacology · December 1989 Although the solvent xylene is suspected of producing nervous system dysfunction in animals and humans, little is known regarding the neurochemical consequences of xylene inhalation. The intent of this study was to determine the effect of intermittent, acu ... Full text Cite

Modulation of neurotoxic esterase activity in vitro by phospholipids.

Journal Article Toxicology and applied pharmacology · February 1989 Neurotoxic esterase (NTE), the proposed molecular site for the initiation of organophosphorus-induced delayed neuropathy, is a membrane-associated enzyme. NTE activity was solubilized from chicken brain microsomal membranes with the detergent 3-[(3-cholami ... Full text Cite

Chromatographic characterization of neurotoxic esterase.

Journal Article Biochemical pharmacology · January 1989 Neurotoxic esterase (neuropathy target enzyme, NTE) is an enzyme whose irreversible inhibition is the apparent first step in the induction of organophosphorus-induced delayed neuropathy. NTE is an integral membrane protein and thus must be solubilized befo ... Full text Cite

Biochemical and morphological validation of a rodent model of organophosphorus-induced delayed neuropathy.

Journal Article Toxicology and industrial health · September 1988 Exposure to certain organophosphates (OPs) produces a delayed degeneration of the longest and largest nerve fibers (OPIDN). Until recently, investigators have used the chicken as the primary experimental model of OPIDN. Although the chicken is extremely se ... Full text Cite

PERSISTENT ACETYLCHOLINESTERASE (ACHE) INHIBITION DISRUPTS NEURONAL INTEGRITY IN RAT HIPPOCAMPUS

Conference JOURNAL OF NEUROPATHOLOGY AND EXPERIMENTAL NEUROLOGY · 1988 Cite

Triphenyl phosphite: in vivo and in vitro inhibition of rat neurotoxic esterase.

Journal Article Toxicology and applied pharmacology · February 1987 Organophosphorus compounds which, after acute administration, inhibit neurotoxic esterase (NTE) by greater than or equal to 65% and undergo a subsequent "aging" reaction, produce a delayed neuropathy characterized by degeneration of large and long nerve fi ... Full text Cite

Biochemical and neuropathological assessment of triphenyl phosphite in rats.

Journal Article Toxicology and applied pharmacology · April 1986 The putative neurotoxicity of the organophosphorus compound triphenyl phosphite (TPP) was examined in Long Evans, adult male rats. Animals were exposed to two 1.0 ml/kg (1184 mg/kg) injections (sc) of TPP spaced 1 week apart and sampled for biochemical and ... Full text Cite

Effects of hypothermia on the in vivo measurement of rapid axonal transport in the rat: a cautionary note.

Journal Article Journal of neurochemistry · April 1986 Rapid axonal transport of glycoproteins was examined in the retinofugal projections of hypothermic and normothermic adult male Long-Evans hooded rats previously receiving intraocular injections of [3H]fucose. The amount of retinal fucosylation appeared nor ... Full text Cite

An in vitro comparison of rat and chicken brain neurotoxic esterase.

Journal Article Fundamental and applied toxicology : official journal of the Society of Toxicology · April 1986 A systematic comparison was undertaken to characterize neurotoxic esterase (NTE) from rat and chicken brain in terms of inhibitor sensitivities, pH optima, and molecular weights. Paraoxon titration of phenyl valerate (PV)-hydrolyzing carboxylesterases show ... Full text Cite

An in vitro comparison of rat and chicken brain neurotoxic esterase

Journal Article Fundamental and Applied Toxicology · April 1986 Full text Cite

The correlation between neurotoxic esterase inhibition and mipafox-induced neuropathic damage in rats.

Journal Article Neurotoxicology · January 1986 The correlation between neuropathic damage and inhibition of neurotoxic esterase or neuropathy target enzyme (NTE) was examined in rats acutely exposed to Mipafox (N, N'-diisopropylphosphorodiamidofluoridate), a neurotoxic organophosphate. Brain and spinal ... Cite

Phenylmethylsulfonyl fluoride protects rats from Mipafox-induced delayed neuropathy.

Journal Article Toxicology and applied pharmacology · November 1985 Initiation of organophosphorus-induced delayed neuropathy (OPIDN) is thought to consist of two molecular events involving the phosphorylation of the target enzyme, neurotoxic esterase, or neuropathy target enzyme (NTE), and a subsequent "aging" reaction wh ... Full text Cite

Body temperature-dependent and independent actions of chlordimeform on visual evoked potentials and axonal transport in optic system of rat.

Journal Article Neuropharmacology · August 1985 Pattern-reversal-evoked potentials (PREPs), flash-evoked potentials (FEPs), rapid axonal transport in the optic system and body temperature were measured in hooded rats, treated with either saline or the formamidine insecticide/acaricide, chlordimeform (CD ... Full text Cite

The relationship between neurological damage and neurotoxic esterase inhibition in rats acutely exposed to tri-ortho-cresyl phosphate.

Journal Article Toxicology and applied pharmacology · March 1985 A rodent model of organophosphorus-induced delayed neuropathy (OPIDN) has been developed using Long-Evans adult male rats exposed to tri-ortho-cresyl phosphate (TOCP). In the present study an attempt was made to relate neurochemical with neuropathological ... Full text Cite