Relapse to uncontrolled drinking after periods of sobriety is a defining characteristic of alcoholism and is often triggered by stress. A new study in rats reports that a specific receptor for a stress-response transmitter may play an important role in stress-induced relapse. The study, a collaboration between scientists at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH), and at Camerino University, Italy, appears online in the Early Edition of the Proceedings of the National Academy of Sciences on October 2, 2006.
"This finding helps untangle the complex interplay of genetic and environmental factors that influence relapse," says NIAAA Director T.-K. Li, M.D. "It also points to potential approaches for treating individuals at risk for relapse."
Anita C. Hansson, Ph.D., a fellow in NIAAA's Laboratory of Clinical and Translational Studies, and other NIAAA scientists worked with Camerino University scientists to examine stress-induced relapse in rats that were bred to have a greater-than-normal preference for alcohol.
"These animals provide an excellent model for identifying genes involved in stress-mediated relapse," says Dr. Hansson. "Not only do they voluntarily consume large amounts of alcohol they also display anxiety and depression-like traits, characteristics that are common among human alcoholics and which indicate a maladaptive response to stress."
A series of behavioral experiments confirmed that the alcohol-preferring rats were more sensitive to stressful situations. For example, they explored a new environment significantly less than did the normal rats, and also remained immobile longer than normal rats did in the novel environment. Each group of rats then learned that, by pressing a bar, they gained access to as much alcohol as they cared to drink. Under these conditions, the alcohol-preferring rats consume more than twice the amount of regular r
Contact: Gregory Roa
NIH/National Institute on Alcohol Abuse and Alcoholism