Abstract
The diuretic effect of azosemide in HgCl2-induced acute renal failure of rats was investigated in comparison with that of furosemide. Acute renal failure was induced by the single s.c. injection of 1, 2, or 4 mg/kg HgCl2; and the test drug was administered 48 hr after treatment with HgCl2. Treatment with HgCl2 resulted in a dose related elevation of plasma urea nitrogen and creatinine levels (mg/dl). In rats with 1 mg/kg HgCl2 induced acute renal failure, azosemide at doses ranging from 10 to 40 mg/kg p.o. dose-dependently increased urinary volume (ml/5 hr) and urinary Na+, K+, and Cl- excretions (mEq/5 hr). In this case, azosemide at 40 mg/kg caused a 3.5-fold increase in urinary volume and 4.5-, 2.1, and 4.1-fold increases in urinary Na+, K+, and Cl- excretions, respectively. Although plasma electrolyte levels were little affected by azosemide, plasma urea nitrogen and creatinine levels were significantly elevated by doses of more than 20 mg/kg of this drug. The diuretic effect of azosemide was more markedly reduced in rats with 2 mg/kg HgCl2-induced acute renal failure than in rats with 1 mg/kg HgCl2-induced acute renal failure. In the case of treatment with HgCl2 of 2 mg/kg, the diuretic effect of azosemide at doses ranging from 40-320 mg/kg p.o. was dose-dependent. However, azosemide had no effect on plasma electrolyte, urea nitrogen, and creatinine levels. The diuretic effect of azosemide in rats given 4 mg/kg HgCl2 was more pronouncedly reduced as compared with that in the case of 2 mg/kg HgCl2. In this case, azosemide at 320 mg/kg brought about a 2.6-fold increase in urinary volume and 4.8-, 4.6-, and 3.9-fold increases in urinary Na+, K+, and Cl- excretions, respectively. This drug had no effect on any plasma parameters. The diuretic effect of azosemide was slightly more potent than those of furosemide in the case of acute renal failure induced by 2 and 4 mg/kg HgCl2.
