Effects of Withania somnifera on Oral Ethanol Self-Administration in Rats

Recent evidence has shown that Withania somnifera Dunal (Ashwagandha or Indian ginseng), an herbal remedy used in traditional medicine, impairs morphine-elicited place conditioning. Here, we investigated the effect of Withania somnifera roots extract (WSE) on motivation for drinking ethanol using operant self-administration paradigms. Wistar rats were trained to self-administer ethanol (10%) by nose-poking. The effects of WSE (25-75 mg/kg) were evaluated on acquisition and maintenance, on ethanol break point under a progressive-ratio schedule of reinforcement and on deprivation effect and reinstatement of seeking behaviours. Moreover, based on the recent suggestion of an involvement of GABAB receptors in WSE central effects, we studied the interaction between WSE and GABAB ligands. The effect of WSE on saccharin (0.05%) oral self-administration was also tested. The results reveal that WSE reduced acquisition, maintenance and break point of ethanol self-administration. WSE also reduced deprivation effect, reinstatement of ethanol-seeking behaviours and saccharin reinforcement. Furthermore, the GABAB receptor antagonist, phaclofen, counteracted WSE’s ability to impair maintenance of ethanol self-administration. These findings demonstrate that WSE, by an action that may involve GABAB receptors, impairs motivation for drinking ethanol and suggest further investigations to ascertain whether Withania somnifera may represent a new approach for the management of alcohol abuse.