PULMONARY AND CENTRAL NERVOUS SYSTEM DAMAGE IN RATS EXPOSED TO HYPERBARIC OXYGEN AND PROTECTION THEREFROM BY GAMMA-AMINOBUTYRIC ACID
Male Wistar rats were exposed to oxygen at 6 atmospheres absolute pressure for periods of 30 and 40 minutes and the effect of the intraperitoneal administration of γ-aminobutyric acid (GABA) (20 mmoles/kg) and glucose (15 mmoles/kg) on the toxic effects of OHP was studied. GABA protected the animals against both gross lung damage and convulsions, but glucose was without effect. Since the accumulation of fluid in the peritoneal cavity was similar for GABA and glucose injections, it would appear that the protective action of GABA was not due to this influx of fluid into the peritoneal cavity brought about by the injected material. All animals having gross pulmonary pathology had suffered severe seizures during the exposure to OHP, but severe convulsions can occur without the incidence of pulmonary pathology. The significance of these observations is discussed.