BEHAVIORAL EFFECTS OF 1-(m-CHLOROPHENYL)PIPERAZINE (m-CPP) IN A RAT MODEL OF TARDIVE DYSKINESIA

Abstract

The present study was designed to monitor the responsiveness of 5-hydroxy tryptamine (5-HT)-2C receptor in rats treated with haloperidol exhibiting tardive dyskinesia (TD). Results show that haloperidol injected at a dose of 1 mg/kg twice a day for two weeks elicited vacuous chewing movements (VCMs). Which increased in a time dependent manner following the drug administration for 3-5 weeks. The behavioral effects of 1-(mchlorophenyl)piperazine (m-CPP) a 5-HT-2C and 5-HT-1B agonist were monitored 2 days after 5 weeks of saline or haloperidol administration. The results show that hypophagic as well as anxiogenic-like effects of mCPP are greater in repeated haloperidol than repeated saline injected animals, while hypolocomotive effects of m-CPP are not different in repeated saline and haloperidol injected animals. Results are discussed in the context of role of 5-HT-2C receptors in the regulation of the activity of dopaminergic neuron and its possible impact on elicitation of TD.