[Effect of psychotropic drugs on cerebral Ca-activated ATPase in vitro]. / Vliianie psikhotropnykh sredstv na Ca-aktiviruemye ATF-azy mozga in vitro.

Neuroleptics, particularly haloperidol and perphenazine, inhibit the activity of brain Ca, Mg-ATPase to a greater extent than the antidepressants benactizin and amphetamine. The actomyosin-like Ca-ATPase is far less sensitive to the psychotropic drugs than Ca,Mg-AtPase. It is suggested that the inhibition of brain Ca,Mg-AtPase by neuroleptics may play a certain role in their antipsychotic action.

[Comparative effect of psychotropic agents on orienting-motor responses and cerebral Na,K-ATPase activity in vivo]. / Sravnitel'noe deistvie psikhotropnykh sredstv na orientirovochno-dvigatel'nye reaktsii i aktivnost' Na, K-ATF-azy mozga in vivo.

Levomepromazine, chlorpromazine (10 and 30 mg/kg), etaperaxine, haloperidol (3 and 10 mg/kg) inhibited the exploratory-motor reactions of rats and the brain Na, K-ATPase activity an hour after their administration. The effects of tranquilizers as well as of antidepressants on the exploratory reactions and on the enzyme activity were not found to stand in a clearcut relation to each other. The stimulating effect of amphethamine (3 mg/kg) was accompanied by activation and suppressive action (10 mg/kg)--by inhibition of the enzyme. It is suggested that the inhibition of the brain Na, K-ATPase activity by psychotropic drugs may play a role in the mechanism of their sedative action.

[Comparative study of the effect of some psychotropic substancces on the activity of brain Na+, K+-ATPase in vitro]. / Sravnitel'noe izuchenie vliianiia nekotorykh psikhotropnykh veshchestv na aktivnost' Na+, K+-ATF-azy mozga in vitro

The activity of Na+, K+-ATPase from bovine brain in vitro was studied as affected by some neuroleptics (levomepromazine, chlorpromazine, perphenazine and haloperidol), antidepressants (imipramine and iproniazid) and psychostimulants (amphetamine) as well as by benactyzine and procaine. The degree of the enzyme inhibition by these drugs estimated by means of I 50 and apparent inhibitor constants (Ki) or rate constants (k) was different. Sensitivity of the brain Na+, K+-ATPase to the drugs decreased in the following order: levomepromazine, chlorpromazine, perphenazine, haloperidol, imipramine, iproniazid, benactyzine, procaine and amphetamine. Competition for the enzyme was revealed between sodium and some of the drugs investigated (levomepromazine, chlorpromazine, perphenazine and impramine) as well as between potassium and other drugs (haloperidol, genactyzine and amphetamine). It is suggested that the inhibition of the brain Na+, K+-ATPase by psychotropic drugs may be a part in the biochemical mechanism of their sedative-tranquilizing activity.

[Isolation of active preparation of Na+, K+-ATPase from cattle brain and study of the role of carboxyl, sulfhydryl and hydroxyl groups].

A method is presented for obtaining the preparation of N+, K+-ATPase from the cattle brain. The specific activity of the preparation is 5 units (mu mole Pi per 1 min) per 1 mg of protein. A water-soluble derivate of carbodiimide is shown to inhibit reversibly both Na+, K+-ATPase and K+-phosphatase. ATP, Na+ and K+ manifest a protective effect against inhibition, and Na+ and K+ revealed a competition with the inhibitor for the enzyme. p-Chloromercuribenzoate inhibits irreversibly Na+, K+-ATPase and K+-phosphatase activities. The substrates ATP and p-nitrophenylphosphate protected these activities against inhibition. The phosphororganic compound O-n-butyl-S-(beta-ethyl-mercaptoethyl)-methyl thiophosphate has no significant effect on the Na+, K+-ATPase and K+-phosphatase activities.