Some properties of erythrocyte Na+-K+-ATPase in essential hypertension

The activity and some allosteric properties of Na+-K+-ATPase in erythrocytes and their membrane preparations (ghosts) from 57 patients with essential hypertension and 36 normotensive controls were studied. To reveal enzyme activity in whole erythrocytes the cells were pretreated with detergent Tween-20. It was found that in the patient erythrocytes the Na+-K+-ATPase activity was 33% less as compared to the control group. Moreover, in the patient erythrocytes the sensitivity of the enzyme to high concentrations of MgCl2 was decreased. In contrast, no analogous changes of the enzyme were revealed in the patient ghosts. It is suggested that the erythrocytes of patients with essential hypertension contain an inhibitor of Na+-K+-ATPase.