DA D2 receptors in the ventral striatum: multiple effects or receptor subtypes?

Abstract

This short review summarizes work from the authors' laboratory regarding electrophysiological roles for two members of the dopamine (DA) D2 receptor family, the D2 and D2 receptors, and their interactions with DA D1 receptors, within the ventral striatum. The inhibitory effects of D2 receptor class agonists on ventral striatal neurons appears to be mediated by D2 as opposed to D2 receptors. This effect requires simultaneous stimulation of the D1 (D1A) receptor. The inhibitory effects of D1 class receptor agonists may involve both the D1 receptor as well as a D1-like receptor not linked to adenylyl cyclase. This effect does not require co-stimulation of a D2 class receptor. The ability of DA to enhance the excitatory effects of glutamate on ventral striatal neurons requires stimulation of both D1 and D2 class receptors. Stimulation of D2 class receptors can either increase or decrease whole cell sodium currents; the particular D2 receptor subtypes responsible for these effects have yet to be established.