[Monoamine oxidase activity and gamma-aminobutyric acid levels in hyperoxia. The effect of clorgyline].

Under conditions of hyperoxia mitochondrial monoamine oxidase (MAO) of the A type from rat brain proved to be able to deaminate gamma-aminobutyric acid (GABA); the transformation in the enzymatic properties appears to be responsible for a decrease in content of the intermediator in brain. Preadministration of chlorgiline (inhibitor of MAO of the A type) into animals before hyperoxygenation prevented completely the GABA content decrease, not affecting the glutamate decarboxylase activity, which was decreased in hyperoxia. At the same time, chlorgiline exhibited the total protective effect increasing 2-fold the period before oxygen convulsions.