[The dynamics and mechanism of changes in the erythrocyte Na, K-ATPase activity of rats under the action of different types of stressors].

The rat erythrocytes' Na, K-ATPase activity was found to drop under the effects of five various stresses: immobilisation, hypothermia, hyperoxia, physical strain, and physical strain against the background of fasting. An endogenous digoxin-like inhibiting agent(s) acting on the Na, K-ATPase seems to appear in the blood plasma of the animals under stress. The suggestion is corroborated by the fact that albumin-less supernatants of the stressed rats' blood plasma are able to inhibit the Na, K-ATPase in the erythrocytes of the control animals.