Decreased M1 muscarinic receptor density in rat amphetamine model of schizophrenia is normalized by clozapine, but not haloperidol.

There is increasing evidence supporting the involvement of the muscarinic-cholinergic system in schizophrenia. We examined the M1 muscarinic receptor density and mRNA expression in brains of a rat amphetamine model of schizophrenia. We also assessed the effect of the model and chronic treatment with haloperidol and clozapine on brain M1 receptor density and gene expression.