[The effect of emotional stress and corticosterone on the activity of monoaminoxidase in the rat brain].
Dissimilar effect of emotional stress on activity of the A and B forms of brain monoamine oxidase (MAO) was found in motionless rats within 1 and 5 hrs: increase in the rate of serotonin deamination catalyzed by MAO A and decrease in the rate of catalyzed by MAO B benzylamine deamination. Preadministration of actinomycin D prevented completely these alterations in activity of MAO A and B developed after 1 hr immobilization; this suggest the regulating effect of genome on MAO activity during stress. Both low 10(-11) 10(-13) M and high 10(-5) 10(-6) M concentrations of corticosterone stimulated the MAO A deamination of serotonin, while the steroid high concentrations inhibited the MAO B deamination of benzylamine either in vitro and in vivo (after intraperitoneal administration of 5 mg/kg). Actinomycin D blocked the stimulating effect of corticosterone at low concentrations on the MAO A activity, whereas the drug did not affect both the alterations in the MAO A and B activities observed after 5 hrs stress and the inhibition of MAO B by high concentrations of corticosterone. The data obtained suggest that corticosterone is not involved in genetic regulation of the MAO A and B activities under conditions of stress, however, the hormone may be of importance in regulation of the enzymatic activity affecting the MAO conformation during the long-term stress.
Popova
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Voĭtenko
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Maslova
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D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000201:enzymology; D003345:Corticosterone / Q000494:pharmacology*; D007103:Immobilization; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013315:Stress, Psychological / Q000378:metabolism*
D008995:Monoamine Oxidase; D003345:Corticosterone
Vliianie émotsional'nogo stressa i kortikosterona na aktivnost' monoaminoksidaz mozga krys.