The role of adrenal or testicular hormones in voluntary ethanol and NaCl intake of crowded and individually housed rats

The effect of adrenalectomy or castration on the ingestive behaviour of 10% ethanol, 0.5 M NaCl, water, and food was investigated in 2 models of increased/high ethanol consumption (1) adult male rats, previously individually housed with low ethanol intake, moved crowded housing and (2) individually housed adult male rats with high ethanol intake in the absence of any known aetiology. In study 1, rats that had been previously individually housed were paired with an animal in a small cage with ad libitum access to 10% ethanol intake, 0.5 M NaCl, water, and food at all times. Rats significantly increased 10% ethanol intake after they were pair-housed. The pairs were either adrenalectomized, castrated or sham operated. Neither adrenalectomy nor castration resulted in a significant change in 10% ethanol intake. 0.5 M NaCl intake was elevated and food intake and body weight were decreased in adrenalectomized rats. In study 2, rats that consumed large amounts of ethanol in the absence of any known aetiology remained in individual housing. Ethanol intake was decreased subsequent to either adrenalectomy or castration; adrenalectomy resulted in an increase in 0.5 M NaCl intake. These results suggest that the influence of adrenal or testicular hormones on ethanol intake is situation dependent. The increase in ethanol intake induced by placing animals in crowded housing appears to be independent of these hormones. (c) 2007 Elsevier Inc. All rights reserved.