Incorporation of intravenously injected (2-(14)C) acetate into tissue lipids of hamsters during the last hour of 3-, 6-, and 24-hour periods of hypothermia.

The in vivo incorporation of total lipid ¹⁴C from 2-¹⁴C]acetate is decreased in kidney, liver, and small intestine tissue from 3-, 6-, and 24-hr hypothermic hamsters compared to tissues from normothermic animals. The length of time in hypothermia affects hamster tissues differently; thus, ¹⁴C activity: decreases with time in kidney; increases with time in liver; and increases at 3 and 6 hr but decreases from 6 to 24 hr of hypothermia in small intestine.Tissues from hypothermic hamsters incorporated a greater percentage of 2-¹⁴C] acetate into free sterols and diglycerides and a smaller percentage into phospholipid than did corresponding tissues from normothermic hamsters.The percentage of total fatty acid ¹⁴C activity found as polyunsaturated fatty acid ¹⁴C activity increases in hypothermic kidney, liver, and small intestine with a decrease in the percentage of ¹⁴C activity measured in the saturated fatty acids. Esterification of fatty acid was inhibited in all tissues taken from hypothermic hamsters.