Whole Body Lipid Metabolism of Rats After Chronic Exposure To Adverse Environments

¹ From the Clayton Foundation Biochemical Institute, University of Texas, Austin, the Southwest Foundation for Research and Education, San Antonio, Texas and the Physiology Department, University of California, Berkeley, California

Specific activities of the total nonsaponifiable lipids, cholestrol, total fatty acids, solid fatty acids and liquid fatty acids, and the liver succinic dehydrogenase activities were determined for adult male Sherman strain rats following chronic exposure (2 months) to cold (2°C), neutral (24°C), or hot (35°C) environments or to discontinuous (4 hr. daily) simulated altitude (18,000 ft., 24°C). By all indices lipid metabolism was elevated in the cold, and by most it was depressed in the heat and altitude. In the latter, however, succinic dehydrogenase activity was elevated. Cholesterol, liquid fatty acids, succinic dehydrogenase activity and the cholesterol/total nonsaponifiable lipid ratios decreased linearly with temperature. The solid/liquid fatty acids ratio was elevated in the heat. The solid fatty acid/cholesterol ratio was temperature independent but was depressed in the altitude group.