BRAIN LIPID-COMPOSITION OF THE HIBERNATING AND ACTIVE GROUND-SQUIRREL, CITELLUS-LATERALIS

1. 1.|Phospholipid analysis of the membranes of the brain of the ground squirrel (Citellus lateralis) reveals significant differences in mean molar values of phospholipid classes between active and hibernating animals. 2. 2.|Specifically, the mol% value of phosphatidylethanolamine decreases while that of phosphatidylcholine increases in the hibernating physiological state. 3. 3.|Additionally, the level of unsaturated fatty acids is increased during hibernation in phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine. 4. 4.|The alterations in steady state levels of phospholipid and fatty acids may contribute to the continued activity of brain cellular membranes at temperatures approaching 0°C. 5. 5.|No difference was found in the level of membrane cholesterol when active and hibernating squirrels were analyzed. © 1979.