Impact of fetal nicotine exposure on development of rat brain regions: critical sensitive periods or effects of withdrawal?

Published

Journal Article

Fetal nicotine exposure evokes alterations in central nervous system structural, neurochemical, and behavioral development. In the current study, the relative importance of critical developmental exposure periods and withdrawal were examined by infusing nicotine to pregnant rats using osmotic minipumps beginning on the fourth day of gestation. Infusions were confined to either the first 8 days (withdrawal on gestational day 13), to nearly all of gestation (withdrawal on gestational day 21), or throughout gestation and continued into the first 2 postnatal weeks. Maternal weight gain was retarded by nicotine, with a hierarchy corresponding to the duration of nicotine exposure. Similarly, fetal and neonatal body weights were unaffected in the group receiving the shortest duration of nicotine exposure, and were less affected by the intermediate infusion regimen than by the longest regimen; brain region weights were reduced significantly only with the longest regimen. Using ODC activity, a sensitive marker for altered brain cell development, we found little change in animals exposed to nicotine in early gestation and undergoing withdrawal on day 13. However, in the groups receiving nicotine through the end of gestation or through gestation and into the postnatal period, ODC activity was significantly elevated. These results indicate that withdrawal from nicotine contributes little, if any, effect either to the growth deficits or to abnormalities of brain cell development. Instead, the most important factor appears to be exposure within the developmental period corresponding to the proliferation of nicotinic receptors and the timing of receptor control of cell replication and differentiation.

Full Text

Duke Authors

Cited Authors

  • Slotkin, TA; Lappi, SE; Seidler, FJ

Published Date

  • 1993

Published In

Volume / Issue

  • 31 / 3-4

Start / End Page

  • 319 - 328

PubMed ID

  • 8490731

Pubmed Central ID

  • 8490731

International Standard Serial Number (ISSN)

  • 0361-9230

Digital Object Identifier (DOI)

  • 10.1016/0361-9230(93)90224-y

Language

  • eng

Conference Location

  • United States