Alcohol-induced accumbal dopamine- and taurine release in female and male Wistar rats, an in vivo microdialysis study

Alcohol use disorder (AUD) is a relapsing brain disorder involving major neurobiological changes. Upon alcohol exposure, dopamine (DA) levels increase in the nucleus accumbens (nAc), a key region of the mesolimbic DA system involved in reward and reinforcement. A concomitant increase in extracellular taurine within the nAc has been shown to be important for the alcohol-induced DA increase. Sex differences in alcohol consumption and in the development of AUD have previously been shown. However, knowledge regarding sex differences in alcohol-induced DA and concomitant taurine release is limited. The aim of this study was to examine potential sex differences in alcohol-induced increases of extracellular levels of DA and taurine within the nAc, following local and systemic alcohol administration. To this end, in vivo microdialysis was performed using male and female Wistar rats. Following systemic alcohol administration, both male and female rats displayed a significant increase of both DA and taurine within the nAc, with no observed sex differences. In contrast, males displayed a significant increase in both DA and taurine following alcohol administration locally into the nAc whilst female rats displayed a blunted DA response and an attenuated taurine increase. Basal levels of DA or taurine did not differ significantly between males and females. The results presented here suggest that local accumbal mechanisms contribute to a greater extent to the alcohol-induced DA increase in male compared to female rats, whilst the response to systemic alcohol administration is similar between sexes.