[Comparative effect of psychotropic agents on orienting-motor responses and cerebral Na,K-ATPase activity 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.