Inhibition of chlorpromazine-induced catalepsy by the 5-HT-1A ligands pindolol and buspirone in mice.

Neuroleptics such as chlorpromazine and haloperidol are capable of inducing catalepsy in rodents. Non-selective 5-hydroxytryptamine (5-HT) antagonists such as methysergide reduce the cataleptic effect of haloperidol. The present study was designed to evaluate the participation of 5-HT-1A receptors in chlorpromazine-induced catalepsy in mice. Pindolol and buspirone, two putative 5-HT-1A receptor ligands, were used. Pretreatment with these drugs reduced the cataleptic effect of chlorpromazine. Clomipramine, a 5-HT neuronal uptake blocker, reversed the inhibitory effect of buspirone. Pretreatment with clomipramine alone caused a potentiation of neuroleptic-induced catalepsy. These results suggest that central 5-HT-1A receptors play an important role in neuroleptic-induced catalepsy in mice.