Na+-H+ exchange activity in renal brush border membrane vesicles in response to metabolic acidosis: The role of glucocorticoids.
نویسندگان
چکیده
Amiloride-sensitive Na+ -H+ exchange activity in brush border membrane vesicles isolated from rat proximal tubule was increased in metabolic acidosis. The enhancement of exchange activity required an intact adrenal gland or glucocorticoid supplements. Ammonium and phosphate excretions were increased during acidosis and these were also largely dependent on an intact adrenal gland or glucocorticoid supplements. Amiloride-insensitive Na+ uptake and passive H+ permeability were not altered by acidosis or the glucocorticoid status of the animal. These findings are consistent with glucocorticoids having an important regulatory role in the kidney by orchestrating the proximal tubular adaptation to metabolic acidosis.
منابع مشابه
Na+-H+ exchange in isolated renal brush-border membrane vesicles in response to metabolic acidosis. Kinetic effects.
Chronic metabolic acidosis increased the Na+-H+ exchange activity in isolated renal brush-border membrane vesicles. Treatment altered the initial rate of Na+ uptake by increasing Vm (acidotic, 15.3 +/- 0.7 nmol of Na+ X mg-1 X 2 s-1; normal, 11.3 +/- 0.9 nmol of Na+ X mg-1 X 2 s-1), and not the apparent affinity KNa+ (acidotic, 10.2 +/- 0.5 mM; normal 10.2 +/- 0.6 mM). Metabolic acidosis result...
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 81 2 شماره
صفحات -
تاریخ انتشار 1984