Stimulation of accumbal GABA receptors inhibits delta2-, but not delta1-, opioid receptor-mediated dopamine efflux in the nucleus accumbens of freely moving rats.

The nucleus accumbens contains delta-opioid receptors that may reduce inhibitory neurotransmission. Reduction in GABA receptor-mediated inhibition of accumbal dopamine release due to delta-opioid receptor activation should be suppressed by stimulating accumbal GABA receptors. As delta-opioid receptors are divided into delta2- and delta1-opioid receptors, we analysed the effects of the GABA receptor agonist muscimol on delta2- and delta1-opioid receptor-mediated accumbal dopamine efflux in freely moving rats using in vivo microdialysis.

In vivo neurochemical evidence that delta1-, delta2- and mu2-opioid receptors, but not mu1-opioid receptors, inhibit acetylcholine efflux in the nucleus accumbens of freely moving rats.

Cholinergic neurons in the nucleus accumbens express delta- and mu-opioid receptors that are thought to inhibit neural activity. Delta- and mu-opioid receptors are divided into delta1- and delta2-opioid receptors and mu1- and mu2-opioid receptors, respectively. We analysed the roles of delta- and mu-opioid receptor subtypes in regulating accumbal acetylcholine efflux of freely moving rats using in vivo microdialysis.