Effects of neurotensin receptor antagonists on the firing rate of rat ventral pallidum neurons

Using anaesthetized adult rats, we compared the effects of i.v. injections of neurotensin receptor antagonists (SR48692 and SR142948), haloperidol and clozapine on neuronal firing rate in the two ventral pallidal areas, SR486 92 (0.5, 1 and 2 mg/kg, i.v.) induced a dose-dependent inhibition of firing rate in two thirds of neurons in the ventromedial part without any effect in the ventrolateral part. These effects are in keeping with the preferenti al neurotensin immunoreactivity distribution reported in the ventral pallid um. The classical antipsychotic drug haloperidol (0.5 mg/kg, i.v.) induced an inhibition of neuronal firing rate in both ventral pallidal areas wherea s the atypical antipsychotic drug clozapine (20 mg/kg, i.v.), like the neur otensin receptor antagonist SR48692, inhibited cell firing only in the vent romedial part. NeuroReport 11:1437-1441 (C) 2000 Lippincott Williams & Wilk ins.