Blood pressure in essential hypertension correlates with the concentration of a circulating inhibitor of the sodium pump

Summary The influence of serum from patients with essential hypertension on the sodium efflux rate constants of human lymphocytes and on the activity of isolated (Na⁺+K⁺)-ATPase was investigated. The ouabain-sensitive sodium efflux rate constant was significantly decreased (p<0.001) in the sera of 19 hypertensives (1.92±0.11 h^–1) compared with the sera of 30 normotensives (2.44±0.07 h^–1). The ouabain-insensitive sodium efflux was unaffected. These results corresponded with a significant difference (p<0.005) of (Na⁺+K⁺)-ATPase activity (1.03±0.04 mU/ml and 0.079±0.06 mU/ml), when an isolated (Na⁺+K⁺)-ATPase was incubated with the sera of 22 normotensives or 18 hypertensives. Both the rate constant of ouabain-sensitive sodium efflux and the (Na⁺+K⁺)-ATPase activity correlated significantly with the diastolic and systolic blood pressure (p<0.001). These data, therefore, demonstrated the close relationship between essential hypertension and the concentration of a circulating inhibitor of the sodium pump.Abbreviations ATP Adenosine triphosphate - EGTA Ethyleneglycol bis(2-aminoethyl)-N,N,N,N-tetraacetic acidThis paper contains an essential part of the thesis of K.M. presented to the Fachbereich Veterinärmedizin, GiessenThis work was supported by the Deutsche Forschungsgemeinschaft, Bonn-Bad Godesberg (Scho 139/16-2) and by the Fonds der Chemischen Industrie, Frankfurt/Main