title: Resistance of erythrocytes of hibernating mammals to loss of potassium during hibernation and during cold storage.
abstract: In two species of hibernators, hamsters and ground squirrels, erythrocytes were collected by heart puncture and the K content of the cells of hibernating individuals was compared with that of awake individuals. The K concentration of hamsters did not decline significantly during each bout of hibernation (maximum period of 5 days) but in long-term bouts in ground squirrels (i.e. more than 5 days) the K concentration of cells dropped significantly. When ground squirrels were allowed to rewarm the K content of cells rose toward normal values within a few hours. Erythrocytes of both hamsters and ground squirrels lose K more slowly than those of guinea pigs (nonhibernators) when stored in vitro for up to 10 days at 5 degrees C. In ground squirrels the rate of loss of K during storage is the same as in vivo during hibernation, and stored cells taken from hibernating ground squirrels also lose K at the same rate. The rate of loss of K from guinea pig cells corresponded with that predicted from passive diffusion unopposed by transport. The actual rate of loss of K from ground squirrel cells was slower than such a predicted rate but corresponded with it when glucose was omitted from the storage medium or ouabain was added to it. Despite the slight loss of K that may occur in hibernation, therefore, the cells of hibernators are more cold adapted than those of a nonhibernating mammal, and this adaptation depends in part upon active transport.
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D001693:Biological Transport, Active; D003080:Cold Temperature; D006224:Cricetinae; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism*; D006019:Glycolysis; D006168:Guinea Pigs; D006605:Hibernation; D010042:Ouabain / Q000494:pharmacology; D010783:Photometry; D011188:Potassium / Q000378:metabolism*; D012589:Sciuridae; D013997:Time Factors
chemical_list: D010042:Ouabain; D011188:Potassium