Histochemical characteristics of nitrergic neuronal system during acute alcohol intoxication and nNOS blockage in the rat lateral septum

Abstract

Annotation. Alcohol is a one of the most frequently consumed substances of abuse, which can cause addiction or alcohol use disorders (AUDs). Alcohol addiction leads to decrease of the life quality of patients and considerable economic burden. Neuronal mechanisms of addiction are intensively studied. One of the most important systems involved in this process is a brain reward system that includes lateral septum (LS). Additionally alcohol consumption changes activity of the neurotransmitter systems including the nitric oxide (NO). Recent studies for blockage of nitric oxide synthase (NOS) for cocaine addiction and late stages of AUDs demonstrated that a group of the substances known as blockers of NOS can be referred to as candidates for alcohol addiction therapy. The aim of our research was to investigate histochemical characteristics of NO-system in LS, its response to acute alcohol intoxication including or excluding neuronal NOS (nNOS) blockage with selective inhibitor – 7-nitroindazole (7-NI). This study involved three experimental groups of animals (control group (n=4), group with acute alcohol intoxication (n=4), group of nNOS blockage with acute alcohol intoxication (n=4)). For statistical analysis, one-way Kruskal-Wallis test was implemented to reveal differences between groups (Matlab, Mathworks). We have identified NOS-positive structures in LS consisting of big neurons, medium/small neurons and nerve fibers. Acute alcohol intoxication activated subpopulations of NOS-positive medium/small neurons and nerve fibers. Moreover, we determined that ethanol-induced changes can be blocked with selective nNOS inhibitor 7-NI.