Effects of Chronic Ethanol Administration and Cold Exposure on Rabbit Adrenocorticoid 11β-Hydroxylase and 18-Hydroxylase Activities

Rabbit adrenocrtical mitochondria contains cytochrome P-450 dependent hydrox-ylase system, capable of catalyzing the hydroxylation as well as other modifications of variety of lipids and foreign compounds, including drugs, pesticides, carcino-gens. Ethanol enhances the activity of the microsomal enzyme system, and cold exposure increases various enzyme activity. The present study investigated the effects of chronic ethanol administration and cold exposure on rabbit adrenocortical mitochondria 11β-and 18-hydroxylase activity, cytochrome P-450 and b₅ and AAF hydroxylation, serum cortisol level and lipid content of the adrenal cortex. The results obtained are : 1) When rabbits were administrated with 15% and 30% ethanol and were exp-osed to cold, the level of adrenocortical mitochondrial 11 β-hydroxylase activity was increased, but 18-hydroxylase activity was slightly increased only in the cold exposure group. This result corresponded with an increase of serum cortisol level. 2) When rabbits were administrated with ethanol and were exposed to cold, the level of cytochrome P-450 in adrenocortical mitochondria was increased, but cytochrome b₅ level did not change. Ring-hydroxylation of AAF did not change, but N-hydroxylation was increased. 3) When rabbits were administrated with ethanol and were exposed to cold, the levels of total cholesterol and triglyceride in adrenal cortex was remarkably incre-ased, but phospholipid level was reduced.