Sodium dependence of early distal H+ secretion in rat kidney
Lopes, M.J.; Malnic, G.
Brazilian Journal of Medical and Biological Research 21(5): 1065-1068
1988
ISSN/ISBN: 0100-879X PMID: 3248235 Document Number: 311947
In order to study the mechanism of H-ion secretion in cortical distal tubules of the rat kidney, the luminal pH and transepithelial potential difference (PD) were measured with double-barrelled, pH-sensitive, resin/reference microelectrodes. Perfusion of peritubular capillaries with low-sodium solutions increased luminal pH by 0.28 +/- 0.024 units. Perfusion of the lumen with 1 mM amiloride increased luminal pH by 0.67 +/- 0.01 units. These changes could not be attributed to modification of transepithelial PD. We conclude that early distal acidification is sodium-dependent, possibly owing to the presence of Na+/H+ exchange.