Effects of spiperone, raclopride, SCH 23390 and clozapine on apomorphine inhibition of sensorimotor gating of the startle response in the rat.

摘要: Previous work suggests that the dopamine agonist apomorphine decreases prepulse inhibition (PPI) of acoustic startle response in rats. To better understand substrates this response, we investigated effects four pharmacologically distinct antagonists on apomorphine-induced loss PPI. Apomorphine (0.5 mg/kg s.c.) markedly decreased PPI for all intervals tested. This effect was reversed by pretreatments with D2 spiperone and raclopride but not pretreatment D1 antagonist SCH 23390. The atypical antipsychotic clozapine exhibited an "inverted-U" shaped dose-response curve, reversing at low doses high doses. High both 23390 independent treatment. baseline amplitude were also differentially modified these drugs: potentiated spiperone- raclopride-pretreated animals, animals pretreated or clozapine. Prepulse has been shown to be impaired humans schizophrenia. Since our present findings suggest activation receptors is responsible rats, overactivity might a substrate deficits