ALPHA(2)-ADRENOCEPTOR ANTAGONISTS AND PROPENSITY TO TAKE ALCOHOLIC BEVERAGES

Rats were maintained on a daily regimen involving a 2h opportunity to take both water and a sweetened alcoholic beverage (12% ethanol, 0.25% saccharin). After 3 weeks on this regimen, rats regularly take substa ntial amounts of alcohol. After stabilization, injections of alpha(2)- adrenergic antagonists were administered, 15 min before the opportunit y to drink. Yohimbine and methoxyidazoxan dose relatedly decreased int ake of alcoholic beverage and increased intake of water. In Experiment 2, a number of rats were taken off the daily regimen for 9 days, then returned to it. Across the first 12 days of the reinstated daily regi men, half the rats received placebo and half methoxyidazoxan. The grou p receiving placebo rapidly returned to taking large amounts of alcoho lic beverage while the group receiving methoxyidazoxan did not. In Exp eriment 3, it was shown that a dose of methoxyidazoxan that decreased intakes of alcoholic beverage did not decrease intakes of other palata ble beverages. In Experiment 4, it was shown that yohimbine persistent ly reduced intakes of alcoholic beverage with daily administration. Th ese results indicate that alpha(2)-antagonists might be effective phar maceutical adjuncts to other treatments for alcohol abuse and alcoholi sm.