Acetate-1-C14 metabolism of white fat from hamsters in cold exposure and hibernation

Abstract

Incorporation of C14 from acetate-1-C14 into lipid and CO2 by epididymal fat from golden hamsters kept at room temperature, acclimated to 5 ± 1 C, in hibernation and arousing from hibernation, was measured in vitro at 37 C. Summer and winter series were compared. The C14O2 production by tissue from control and acclimated animals was similar but the C14O2 production of tissue from hibernating and arousing hamsters was significantly greater than that from acclimated animals. There was a large increase in the lipid-C14 of tissue from cold-acclimated animals and this increase persisted into hibernation but was slightly depressed in tissue from arousing animals. Many acclimated and all hibernating hamsters had involuted testes and a greater incorporation of C14 into lipid than those with noninvoluted testes. A greater percentage of hamsters hibernated in the cold room during the winter and at this time the incorporation of C14 into lipid by the fat pad was greater than in the summer.