The effect of mineralocorticoid deficiency on renal concentrating and diluting capacity.
To examine the effect of mineralocorticoid deficiency on sodium transport by the ascending limb of the loop of Henle, free water clearance and reabsorption were measured in the same six dogs under conditions of aldosterone deficiency and mineralocorticoid sufficiency.  Aldosterone deficiency was induced by bilateral adrenalectomy with dexamethasone replacement.  H2O/100 ML GFR ranged from 4.0 to 19.5 in the aldosterone deficient dogs and 4.5-18.6 in the mineralocorticoid sufficient dogs.  H2O/100 ML GFR plotted against V/100 ML GFR showed no significant difference between the two groups.  H2O/100 ml GFR ranged from 1.2 to 6.5 in the mineralocorticoid sufficient group and 2.4-8.5 in the mineralcorticoid sufficient group and 2.4-8.5 in the aldosterone deficient group. TC-H2O/100 GFR plotted against Osm/100 ml GFR revealed no significant urine concentration in the mineralocorticoid sufficient group was 1356 mOsm/kg plus or minus 254 (SD) and 1386 mOsm/kg plus or minus 331 (SD) for the aldosterne deficient group; the difference is not significant.  This study failed to demonstrate any effect of aldosterone deficiency on renal concentrating and diluting capacity and thus provides inferential evidence against an effect of aldosterone on ascending limb sodium reabsorption.
D000315:Adrenalectomy; D000450:Aldosterone / Q000172:deficiency* / Q000494:pharmacology*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D003900:Desoxycorticosterone; D003907:Dexamethasone; D004231:Diuresis; D004285:Dogs; D005919:Glomerular Filtration Rate; D007668:Kidney / Q000503:physiopathology*; D007671:Kidney Concentrating Ability; D008138:Loop of Henle / Q000187:drug effects / Q000503:physiopathology; D009994:Osmolar Concentration; D012964:Sodium / Q000378:metabolism*; D014867:Water / Q000378:metabolism
D014867:Water; D003900:Desoxycorticosterone; D000450:Aldosterone; D003907:Dexamethasone; D012964:Sodium