The action of oxygen and oxygen at high pressure on inhibitory transmission.

Published

Journal Article

The effect of 100% oxygen at ambient pressure, 100% oxygen at 1.7 Atmospheres Absolute (ATA), 100% oxygen at 5.1 ATA, helium at 1.7 ATA and helium at 5.1 ATA on inhibitory synaptic transmission was studied using the lobster walking leg neuromuscular preparation. Exposure to 100% oxygen at ambient pressure, at 1.7 ATA or at 5.1 ATA produced a decrease in inhibitory transmission manifest as a fall in inhibitory synaptic conductance (Ginh). The largest decrease in Ginh was seen in 100% oxygen at ambient pressure, while a progressively smaller decrease was seen in 100% oxygen at 1.7 ATA and 5.1 ATA, respectively. Also associated with 100% oxygen at ambient pressure was the disappearance of inhibitory junction potentials. Pressurization with helium produced a fall in Ginh at 5.1 ATA but no change or a slight increase at 1.7 ATA. The action of either 100% oxygen at ambient and at 1.7 or 5.1 ATA or helium at 1.7 or 5.1 ATA was shown to be on presynaptic parameters since the percent decrease in Ro induced by exogenous application of gamma-aminobutyric acid (GABA), the inhibitory transmitter, was the same in either 100% oxygen at ambient pressure, 100% oxygen or helium at 1.7 ATA and 5.1 ATA. The similarity in action of oxygen to the action of isoniazid, a known glutamic acid decarboxylase (the enzyme that catalyzes the production of GABA) inhibitor in the same preparation suggests that one possible site of oxygen action is on GABA production.

Full Text

Duke Authors

Cited Authors

  • Colton, CA; Colton, JS

Published Date

  • January 1, 1986

Published In

Volume / Issue

  • 364 / 1

Start / End Page

  • 151 - 158

PubMed ID

  • 3004647

Pubmed Central ID

  • 3004647

Electronic International Standard Serial Number (EISSN)

  • 1872-6240

International Standard Serial Number (ISSN)

  • 0006-8993

Digital Object Identifier (DOI)

  • 10.1016/0006-8993(86)90995-9

Language

  • eng