Saturday, October 13, 2012: 9:20 AM
Hall 4E/F (WSCC)
The link between stress and substance abuse is well documented. Individuals exposed to severe stressors have a higher propensity to abuse controlled substances. Yohimbine is an alpha-2 adrenoceptor antagonist that produces an unpleasant stress response in both humans and rodents. To date, most research using yohimbine has focused on the reinstatement of ethanol consumption on previously-treated animals. However, the effects of yohimbine on c-Fos expression on brain regions involved in the pleasurable sensations following alcohol intake remain unclear. It is hypothesized that mice subjected to a yohimbine treatment will display a higher ethanol preference and widespread patterns of c-Fos expression in their nucleus accumbens. c-Fos is a marker of neural activity that is also highly reactive to stress. Mice will be injected with yohimbine (2 mg/kg) before being subjected to a time-restricted 2-bottle choice paradigm (10 % w/v ethanol and water). To determine the effects of stress-mediated alcohol abuse on neural activity of these mice, two brain regions that play a significant role in the development of addiction, the prefrontal cortices and nuclei accumbens, will be removed. A dose-dependent increase in levels of c-Fos is expected in the prefrontal cortices and nuclei accumbens of yohimbine-treated mice as detected by Western Blotting analysis. The intent of this study is to further clarify the molecular mechanisms involved in the initiation of stress-mediated alcohol preference and abuse.