A pharmacological dose of estradiol can enhance appetites for alcoholic beverages

Each of 30 female Sprague-Dawley rats were given 2 mg of estradiol valerate (EV), 30 others were given placebos. EV is a preparation that delivers estradiol for more than 12 days, but probably less than 20. Fifteen days later, the females had the opportunity to take sweetened alcoholic beverage 24 h a day across 25 days. Subsequently, they could self-administer other alcoholic beverages, including one of only alcohol and water. After a period of abstinence, rats had another opportunity to take sweetened alcoholic beverage (94 to 96 days after the single injection of EV). With every measurement, rats given EV consumed significantly more ethanol than controls. For example, mean of measurements representing daily intake for the fourth week of availability of palatable alcoholic beverage for placebo-treated=5.29 grams of ethanol per kilogram of bodyweight (g'E/kg); for EV-treated=8.13 g'E/kg; P=.003. The data support the conclusion that pharmacological doses of estradiol can induce marked, enduring changes in appetite for alcoholic beverages.