MUSCARINIC ACETYLCHOLINE M2 RECEPTORS INCREASE IN CHOLINERGIC INTERNEURONS OF THE NUCLEUS ACCUMBENS FOLLOWING BINGE ALCOHOL DRINKING IN C57BL/6J MICE

Alcoholism is a complex disease that affects millions of people in the world. While many animal models of alcoholism exist, it is extremely difficult, if not impossible, to capture every aspect of alcoholism in an animal model. Utilizing an animal model that is reported to produce pharmacologically significant levels of blood ethanol concentration, the present study examined the cholinergic interneurons in the nucleus accumbens, a brain region that is affected by drugs of abuse including alcohol. Cholinergic interneurons in the nucleus accumbens were of particular interest in this study since previous findings have reported that these neurons are involved in binge alcohol drinking. Specifically, cholinergic neurons are shown to possess muscarinic M2 receptors that autoregulate acetylcholine release. The study presented in this thesis examined the effect of binge alcohol drinking on muscarinic M2 autoreceptors on accumbal cholinergic interneurons. The present findings report an increase in the number of M2 receptor-positive cholinergic neurons in the nucleus accumbens following binge alcohol drinking in C57BL/6J mice. Binge alcohol drinking, however, had no significant effect on the volume of the nucleus accumbens or the volume of accumbal cholinergic interneurons. These findings may provide the groundwork for future studies that may aim to develop novel muscarinic receptor subtype targeted treatments for alcohol abuse and alcoholism.