ABNORMALITIES OF ERYTHROCYTE SODIUM-TRANSPORT IN REFLUX NEPHROPATHY

Hypertension is a complication of reflux nephropathy commonly occurrin g during adolescence and young adult life, We studied cellular sodium transport in an adolescent cohort with this condition as abnormal sodi um transport is a feature of human hypertension. Thirty males and 52 f emales with reflux nephropathy, (median age 20.3 years) had erythrocyt e ouabain sensitive sodium-potassium ATPase (Na/K ATPase) pump site nu mber (Bmax) and red cell sodium concentration (RBC Nac) measured in 19 88, Six years later, 55 of those had red cell sodium-lithium counter t ransport (LOT) measured, On both occasions, their renal function and b lood pressure (BP) were determined. Bmax in the study group (median 10 .3 nmol/l) was significantly less than that of controls (median 11.45 nmol/l). Nine patients who were diagnosed as having hypertension durin g the 6 year study period appeared to have a lower Bmax compared with that of normotensives in the group. RBC Na+ and LCT of the study group were not significantly different from that of controls. The Na/K ATPa se activity is diminished, and sodium-lithium counter transport is unc hanged in reflux nephropathy, Further study is needed to ascertain the link between these observations and the onset of high BP.