Free-choice ethanol consumption by rats: effects of ACTH4-10.

The individual and interactive effects of immobilization stress, ACTH11-24 and ACTH4-10 on the free-choice consumption of ethanol in rats were studied. Stress and ethanol both result in activation of the HPA axis and release of ACTH1-39. The animals were offered a two-bottle choice consumption of 0.2% saccharin and 10% ethanol. They were exposed to immobilization stress or IP injections of ACTH4-10 or ACTH11-24 on an irregular, unpredictable schedule. Stress resulted in a decrease in ethanol consumption during the stress period while ACTH11-24 was devoid of any effect. The ACTH4-10 fragment produced an almost complete block of ethanol consumption during the injection period. Saccharin consumption was not affected by any of the above treatments. These results suggest an important role for ACTH4-10 (produced from ACTH1-39) in ethanol consummatory behavior in rats.