MOLECULAR ATTRIBUTES OF DOPAMINE-RECEPTORS - NEW POTENTIAL FOR ANTIPSYCHOTIC DRUG DEVELOPMENT

The neurotransmitter dopamine (DA) plays a central role in the control of motor function, emotional states, and endocrine physiology. The di scovery that schizophrenic symptoms can be alleviated by neuroleptic d rugs and the finding that these drugs interact at dopamine receptors h as indicated involvement of the dopamine system in schizophrenia. The dopamine system has recently been shown to rely on the activation of f ive distinct subtypes of DA receptors (D1-D5) identified by molecular cloning, and pharmacological studies have specifically implicated the D2-like receptors (D2R, D3R and D4R) in antipsychotic action. In addit ion, the localization of D3R and D4R expression in the mesolimbic/meso cortical DA pathways is consistent with their proposed involvement in affective behaviour, and suggests that drugs developed specifically fo r these receptor subtypes might have potent antipsychotic activity wit h a lower propensity for extrapyramidal, endocrine, and cognitive side -effects.