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

Abstract

Hyperbaric oxygen (HBO₂) breathing induces generalized tonic and clonic seizures through poorly understood mechanisms. The purpose of the research was to evaluate the mechanisms of involvement of monoamine oxidase (MAO) in the development of hyperbaric oxygen seizures. In rats placed in a pressure chamber under an oxygen pressure of 5 ATA, convulsive reactions were analyzed after the administration of pyrazidol, an MAO-A inhibitor, and pargyline, an MAO-B inhibitor. Studies have shown a decrease in the activity of MAO isoforms in HBO₂ as well as a delay in the development of seizures in animals with inhibition of MAO-A and MAO-B. The level of GABA in the brain decreased with HBO₂, and inhibition of MAO-B with pargyline prevented the decrease in the inhibitory transmitter. The results indicate that MAO isoforms play an important role in regulating epileptogenesis in extreme hyperoxia. Hyperbaric oxygen, inhibiting the catalytic activity of MAO by transforming its molecular structure, leads to disruption of the regulation of the exchange of monoamine neurotransmitters and a decrease in the level of GABA in the brain, which together leads to an imbalance of excitation/inhibition processes in the central nervous system, which is the basis for the development of oxygen epilepsy.