EFFECTS OF COLD ACCLIMATION AND AROUSAL FROM HIBERNATION ON BROWN FAT LIPID AND PROTEIN IN GOLDEN HAMSTER (MESOCRICETUS AURATUS)

1. 1. Total lipid and protein are monitored in interscapular, cervical and thoracic brown fat deposits from normal control, cold-acclimated, hibernating and newly aroused golden hamsters (Mesocricetus auratus). 2. 2. During cold acclimation total lipid declines significantly while protein content increases markedly in all brown fat deposits. In contrast to interscapular and cervical deposits, thoracic brown fat contains a higher percentage of protein than lipid after cold acclimitation. 3. 3. After cold acclimation brown fat retains the same lipid and protein levels in hamsters exposed to very short and very long hibernating periods. 4. 4. Newly aroused hamsters show little or no evidence of loss of brown fat lipid during arousal from hibernation. This contrasts with findings of other workers that ground squirrels lose a substantial percentage of brown fat lipid during arousal. © 1969.