Effect of repeated treatment with topiramate on voluntary alcohol intake and beta-endorphin plasma level in Warsaw alcohol high-preferring rats

RATIONALE: Pharmacological treatment currently used for alcohol dependence is not sufficient for the all patients, and there is a crucial need to find more effective treatments. Recent studies indicate that topiramate is likely the most promising new medication for alcohol dependence. The rationale for topiramate as treatment for alcohol addiction is based on its multifaceted neurochemical activity that targets multiple neural pathways. OBJECTIVES: This study aims to assess the effect of repeated treatment with topiramate on voluntary alcohol intake and beta-endorphin plasma level in rats selectively bred for high alcohol preference. METHODS: Initially, Warsaw high preferring rats (N = 50) were given a 24-h/day free choice between a 10 % (v/v) alcohol solution and water for three consecutive weeks. Subsequently, rats were administered with topiramate (40 or 80 mg/kg b.w.) or vehicle for 14 days and ethanol intake was measured daily. Subsequently, we examined the effects of topiramate on plasma beta-endorphin levels, while alcohol was available and when it was not available for an extended period time. RESULTS: We observed significantly increase in the levels of beta-endorphin in rats with free access to alcohol both in a topiramate- or vehicle-treated group. However, in topiramate-treated group, a voluntary consumption of alcohol diminished in comparison with the vehicle-treated rats. CONCLUSION: The results from this study indicated that topiramate reduces voluntary alcohol intake and support our previous findings that the increase of beta-endorphin level is responsible at least partly for the effectiveness of drugs in treating the alcohol addiction.