Effect of acute and chronic conditions of over-crowding on free choice ethanol intake in rats.

Male albino rats of Wistar strain were exposed to overcrowding stress in two different groups for a period of seven days. One group of rats was kept under stress for six hours per day (acute stressed group) and the other group rats was kept under stress continuously (chronic stressed group). The effect of these acute and chronic stresses on voluntary alcohol (2% w/v) intake was monitored during the 7 days of stress exposure, and ethanol preference and total ethanol intake in terms of g/kg body weight were also studied. A significant increase in ethanol preference and ethanol intake was observed in one-day and 7 days chronic stressed group. No significant increase in ethanol intake was observed in acute stress. Thus a short lasting stressor may not increase ethanol-drinking behavior, whereas when animals were exposed to more intense stressor continuously for 7 days, an increase in voluntary drinking behavior may be seen.