Effect of exposure to an alcohol diet for 10 days on the ability of interleukin-1 beta to release ACTH and corticosterone in the adult ovariectomized female rat.
Adult ovariectomized female rats were fed an alcohol diet for 10 days. Animals fed ad libitum, or fed an isocaloric diet (pair-fed), were also included in all experiments. The intravenous injection of interleukin-1 beta caused dose-related increases in plasma adrenocorticotropic hormone (ACTH) levels in all three groups of rats. However, alcohol-fed animals showed a significant blunting of their ACTH, but not corticosterone response, in comparison with rats fed ad libitum or pair-fed. In contrast, corticotropin-releasing factor (CRF) injection caused overall statistically comparable ACTH secretory rates in all animals, although small differences were observed in some cases. Exposure to mild electroshocks for 30 min significantly increased ACTH values in all animals, but alcohol-fed rats again showed blunted release. In this paradigm, pair-fed animals exhibited a response that was intermediate between that of the ad libitum and alcohol-fed groups. We conclude that chronic alcohol consumption decreases the response of the hypothalamic-pituitary axis to cytokines and mild footshocks. This suggests that the activity of both CRF nerve terminals in the median eminence, and of CRF perikarya in the hypothalamus, is inhibited by this treatment, although pituitary responsiveness to CRF appears unchanged.