A lot of research concerning alcoholism and other forms of substance abuse uses animal models. With respect to alcoholism, however, these animal models show one big difference with ‘real’ alcoholics: when given the choice, the animals (often mice) still prefer non-alcoholic drinks, such as water. So, unless alcohol is the only choice, or is administered by the experimenters, they are not really alcoholics.
Until now. A new study, published in Addiction Biology, reports the selective breeding of genuine mice alcoholics. Selectively bred for 40 generations by researchers from Indiana University – Purdue University Indianapolis, the mice lines are known as High Alcohol Preferring (or HAP) mice. The animals were specifically bred for their intake of 10% ethanol.
Given a free choice between alcohol and water, the HAP mice drink alcohol at a rate higher than the rate at which they metabolize alcohol. On average, they reach blood-alcohol levels of 260mg/dl daily, which is, translated into human terms, about three times the legal driving limit and approximately the level found in severe alcoholics. It takes six to seven hours for these HAP mice to reach the highest levels of intoxication.
It is thought that this line of mice might prove useful in elucidating the brain mechanisms involved in alcohol consumption, as well as the effects of excessive alcohol on the brain itself. And eventually, this might contribute to treatments and therapies.
The researchers conclude:
Free-choice drinking demonstrated by the HAP1 and cHAP lines may provide a unique opportunity for modeling the excessive intake that often occurs in alcohol-dependent individuals, and allow for exploration of predisposing factors for excessive consumption, as well as the development of physiological, behavioral and toxicological outcomes following alcohol exposure.
(Source: MU Science Blog)
References
Matson, L.M. and Grahame, N.J. (2011). Pharmacologically relevant intake during chronic, free-choice drinking rhythms in selectively bred high alcohol-preferring mice. Addiction Biology. Published online 29 November. Doi:10.1111/j.1369-1600.2011.00412.x.
Science@iupui, News. New Strain of Lab Mice Mimic Human Alcohol Consumption Patterns. 8 December.
