Behavioral effects of l-[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-[m-chlorophenyl]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 m-CPP 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