[Renal sodium-potassium ATPase during adaptation to different factors in the environment of rats and Citellus flavus susliks].

Seasonal changes in the activity of microsomal transport Na, K-ATPase from cortical, medullar and papillary zones of the kidney have been studied in rats kept under constant laboratory conditions. Maximum activity of the enzyme was found in all kidney zones during May and December-January periods (up to 70%). The lowest level of the activity was observed in summer, especially in July (up to 30-40%). In the ground squirrels, the activity of transport ATPase decreased significantly in all kidney zones within 3 weeks of keeping the animals in the laboratory.