Anxiolytic-like, anorexic, adipsogenic and anti-alcohol intake effects of acute taurine administration into dorsal periaqueductal gray of female and male adult Wistar rats

Abstract

Taurine (TAU, 2-aminoethane sulphonic acid) is a semi-essential β sulfonated amino acid, one of the most abundant free amino acids in the body and the mammalian brain. Most studies on taurine have demonstrated its beneficial role at acute doses, administered either systemically or i.c.v., on numerous disease models and an inhibition of alcohol intake. The periaqueductal gray (PAG) is a key vertebrate midbrain structure for integrated defensive responses, including those representing stress and anxiety-like behavior. A strong relationship between anxiety and alcohol intake, besides the critical role of dorsal periaqueductal gray (D-PAG) in behavioral defensive and consummatory responses, has been shown. This study aimed to assess the pharmacological effects of taurine administration into D-PAG on anxiety-like behavior through the elevated plus maze test, as well as consummatory behavior through food, water, and alcohol intake and preference. Both female and male rats, either alcohol naïve or forced ethanol intake (since juvenile age with a chronic intermittent access model), were implanted with cannulae on the right side of D-PAG. We found that administering taurine into D-PAG elicits an anxiolytic-like effect and reduces food and water intake in all groups. Furthermore, taurine inhibits alcohol consumption by adult Wistar rats previously exposed to alcohol.