Abnormalities of erythrocyte sodium transport in reflux nephropathy.
Hypertension is a complication of reflux nephropathy commonly occurring during adolescence and young adult life. We studied cellular sodium transport in an adolescent cohort with this condition as abnormal sodium transport is a feature of human hypertension. Thirty males and 52 females with reflux nephropathy, (median age 20.3 years) had erythrocyte ouabain sensitive sodium-potassium ATPase (Na/K ATPase) pump site number (Bmax) and red cell sodium concentration (RBC Na+) measured in 1988. Six years later, 55 of those had red cell sodium-lithium counter transport (LCT) measured. On both occasions, their renal function and blood 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 during 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 ATPase activity is diminished, and sodium-lithium counter transport is unchanged in reflux nephropathy. Further study is needed to ascertain the link between these observations and the onset of high BP.
Goonasekera
C D
CD
Division of Clinical Sciences, Institute of Child Health, London, UK.
Jardim
H
H
Shah
V
V
Dillon
M J
MJ
D000293:Adolescent; D000328:Adult; D017920:Antiporters / Q000097:blood; D001692:Biological Transport; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D012964:Sodium / Q000097:blood*; D014552:Urinary Tract Infections / Q000097:blood* / Q000209:etiology*; D014718:Vesico-Ureteral Reflux / Q000150:complications*
D017920:Antiporters; C045885:sodium-lithium countertransporter; D012964:Sodium