Mechanisms of Monoamine Oxidase Involvement in the Development of Hyperbaric Oxygen Seizures

Hyperbaric oxygen (HBO₂) breathinginduces generalized tonic and clonic seizures through poorly understoodmechanisms. The purpose of the research was to evaluate the mechanismsof involvement of monoamine oxidase (MAO) in the development ofhyperbaric oxygen seizures. In rats placed in a pressure chamberunder an oxygen pressure of 5 ATA, convulsive reactions were analyzedafter the administration of pyrazidol, an MAO-A inhibitor, and pargyline,an MAO-B inhibitor. Studies have shown a decrease in the activityof MAO isoforms in HBO₂ as well as a delayin the development of seizures in animals with inhibition of MAO-Aand MAO-B. The level of GABA in the brain decreased with HBO₂,and inhibition of MAO-B with pargyline prevented the decrease inthe inhibitory transmitter. The results indicate that MAO isoformsplay an important role in regulating epileptogenesis in extremehyperoxia. Hyperbaric oxygen, inhibiting the catalytic activityof MAO by transforming its molecular structure, leads to disruptionof the regulation of the exchange of monoamine neurotransmittersand a decrease in the level of GABA in the brain, which togetherleads to an imbalance of excitation/inhibition processes in thecentral nervous system, which is the basis for the development of oxygenepilepsy.