Hgcl2-induced acute renal failure in the rat. Effect of water diuresis, saline loading, and diuretic drugs.

A variety of pretreatment-treatment protocols were applied to rats with ARF induced by the subcutaneous injection of 6 mg of HgCl2 per kilogram body weight. Renin depletion induced by DOCA-saline pretreatment was associated with protection against HgCl2-induced ARF only when the saline diuresis was maintained by drinking 1% NaCl after injury. Twenty-four dehydration followed by free access to tap water annihilated the protective effect of DOCA-saline pretreatment despite maintained depletion of renal renin. Continuous intravenous loading with saline and furosemide, although increasing renal renin levels, afforded as much protection as saline loading alone. Ethacrynic acid, which did not increase salt excretion in our rats, as well as water diuresis, failed to be protective. A loose correlation was found between he amount of histological damage to the convoluted parts of the proximal tubules and the degree of renal functional impairment. Thus protection against HgCl2-induced ARF was independent of the renal renin level but closely related to urinary NaCl excretion after the injury. Saline diuresis could act by relieving or preventing tubular obstruction.