Abstract
New therapies are needed for alcohol abuse, a major public health problem in the U.S. and worldwide. There are only three FDA-approved drugs for treatment of alcohol abuse (naltrexone, acamprosate and disulfuram). On average these drugs yield only moderate success in reducing long-term alcohol consumption. Electroacupuncture has been shown to alleviate various drugs of abuse, including alcohol. Although previous studies have shown that electroacupuncture reduced alcohol consumption, the underlying mechanisms have not been fully elucidated. ΔFosB and FosB are members of the Fos family of transcription factors implicated in neural plasticity in drug addiction; a connection between electroacupuncture's treatment of alcohol abuse and the Fos family has not been established. In this study, we trained rats to drink large quantities of ethanol in a modified intermittent access two-bottle choice drinking procedure. When rats achieved a stable baseline of ethanol consumption, electroacupuncture (100 Hz or 2 Hz, 30 min each day) was administered at Zusanli (ST36) for 6 consecutive days. The level of FosB/ΔFosB in reward-related brain regions was assessed by immunohistochemistry. We found that the intake of and preference for ethanol in rats under 100 Hz, but not 2 Hz electroacupuncture regiment were sharply reduced. The reduction was maintained for at least 72 hours after the termination of electroacupuncture treatment. Conversely, 100 Hz electroacupuncture did not alter the intake of and preference for the natural rewarding agent sucrose. Additionally, FosB/ΔFosB levels in the prefrontal cortex, striatal region and the posterior region of ventral tegmental area were increased following excessive ethanol consumption, but were reduced after six-day 100 Hz electroacupuncture. Thus, this study demonstrates that six-day 100 Hz electroacupuncture treatment effectively reduces ethanol consumption and preference in rats that chronically drink excessive amount of ethanol. This effect of electroacupuncture may be mediated by down-regulation of FosB/ΔFosB in reward-related brain regions.