Antidepressant profile of 9-methyl-2[-3-(4-phenyl-1-piperazinylpropyl)]-1,2,3,4-tetrahydro-beta- carbolin-1-one (B-193)

A potential antidepressant activity of B-193 was studied in mice and rats. In in vitro studies B-193 did not affect the uptake of NA and 5-HT. In in vivo models the tested compound did not influence the reserpine-induced hypothermia, hypoactivity and ptosis, the stimulating action of L-DOPA, the apomorphine-induced hypothermia. On the other hand, it produced a positive effect in the despair test. When given repeatedly, it evoked adaptive changes in brain neurotransmitter receptors, i.e. it decreased the density of beta-adrenoceptors and increased the number of alpha 1 ones; those changes were accompanied with functional alternations in the reactivity of those receptors: an attenuated behavioral reaction to salbutamol and enhanced aggressiveness induced by a high dose of clonidine. Furthermore, B-193 administered repeatedly enhanced hyperlocomotion induced by amphetamine but did not influence the stereotypy induced by apomorphine. These results indicate that B-193 possesses properties characteristic for atypical antidepressants.