[Changes in the properties of the enzymes of energy allowance resulting from heat shock in lake frogs].

A study was made of the activity and heat resistance of preparations of Na, K-ATPase, Mg-ATPase and succinate dehydrogenase of the lake frog R. ridibunda caused by the heat shock of animals. A decrease in the activity and an increase in the heat resistance of all the three enzymes studied were observed. The level of individual correlations between these parameters remained unchanged. An increase in the heat resistance of Na, K-ATPase occurs at the expense of a higher threshold of its thermal inactivation without changes in the affinity of this enzyme to Na+ and K+. Under discussion is the question of the functional significance of the changes observed.