[Type A and B monoamine oxidase activity in hyperbaric oxygenation].

Substrate specificity of monoamine oxidase (MAO) of the A type from rat brain and liver tissues was altered after exposure of rats to an increased oxygen pressure [4 ati O2, 1 hr]. Simultaneously with a decrease in monoamine deaminating activity the enzyme acquired an ability to deaminate several substances, which are not MAO substrates in normal state, in particular, aminosugars. Activity of MAO of the B type was not altered in brain under hyperoxia. Alterations in catalytic properties of MAO of the A type were apparently important in development of the oxygen intoxication.