Relationship between plasma renin activity and distal nephron sodium delivery and reabsorption in man
Iaina, A.; Thomsen, K.; Goldfarb, D.; Serban, I.; Gavendo, S.; Kapuler, S.; Lusky, A.; Eliahou, H.E.
Israel Journal of Medical Sciences 23(12): 1205-1209
1987
ISSN/ISBN: 0021-2180 PMID: 3326859 Document Number: 294129
The relation between plasma renin activity and distal tubular Na delivery and reabsorption was examined in man. Distal Na delivery and reabsorption were measured during hypotonic volume expansion by the free water clearance method, or during hydropenia or isotonic volume expansion by the lithium clearance method. The maximum water diuresis method and the lithium clearance method both showed a negative correlation between plasma renin activity and distal Na delivery and reabsorption. Only with the lithium clearance method, however, was it possible to measure plasma renin activity, distal Na delivery and reabsorption in hydropenia without disturbances of water and electrolyte balance and plasma renin activity. In hydropenia the plasma renin activity was higher and the fractional distal Na delivery and reabsorption lower than during volume expansion. The results support the idea that sodium chloride reabsorption at the macula densa region is negatively correlated with plasma renin activity in man.