THE RELATION OF CELLULAR SULFHYDRYL CHANGES TO THE RENAL ACTION OF THE ANTIDIURETIC HORMONE

¹ Department of Pharmacology, State University of New York, Upstate Medical Center, Syracuse, New York

Effects of antidiuretic hormones on the protein-bound sulfhydryl (PBSH) and disulfide (PBSS) of the cytoplasm of renal cells have been studied by a cytophotometric technique. The major effect of antidiuretic hormone (ADH) is on the luminal side of renal tubular cells and only with large doses and prolonged exposure to the hormone do the PBSH changes appear also at the basilar portion of the cells. Dose-response determinations show that Pitressin, lysine vasopressin and arginine vasopressin produced significant PBSH decreases in doses of 0.1 to 1.0 mU/100 g of rat b.wt. Antidiuresis as determined in the rat correlates with the PBSH but not with the PBSS changes. Evidence is presented which indicates that PBSS changes are related to the recovery from antidiuresis. Dehydration produced PBSH changes in normal rats but not in rats with diabetes insipidus or hypophysectomized rats. Injection of ADH into rats with diabetes insipidus produced a reduction in PBSH only in the cells of the ascending limb of Henle and distal convoluted tubules. This is in contrast to the effects seen in normal rats, in which PBSH effects were seen along the whole renal tubular system. In dogs, infusion of ADH produced an antidiuresis and PBSH changes in the cells of the ascending limbs of Henle and distal convoluted tubules. Injection of maximally effective doses of the mercurial diuretic, inersalyl, and ADH show that the effects of PBSH are additive, thus indicating that the mercurial- and hormone-induced PBSH changes occur at different PBSH groups. Injection of hypertonic, but not of isotonic, saline into the carotid artery of rats produced a typical renal cellular PBSH reduction, indicating release of ADH. The results obtained suggest that ADH produced an effect on PBSH which may be related to the membrane permeability changes observed in the kidney.