Examination of the ouabain-sensitive Na-K pump in essential hypertensive children of normal body weight.

The ouabain-sensitive Na-K pump of erythrocytes was examined in 17 normotensive and 15 essential hypertensive children aged 6-16 years. Children who proved to be fat according to skinfold measurements were excluded from the examinations. The activity of the ouabain-sensitive Na-K pump was assessed by measuring the ratio of Na-ion efflux and K-ion influx through the erythrocyte membrane previously treated with para-chloro-mercury benzol sulphonate. In essential hypertensive children the ratio of the Na/K fluxes was found to be characteristically 5.8 +/- 2.0, showing a mathematically significantly more active (p less than 0.05) Na-K pump function than in the control group 9.6 +/- 5.8. According to the results, however, the method is suitable only for the separation of groups and not of individuals.