Importance of NO/EDRF for glomerular and tubular function: Studies in the isolated perfused rat kidney

摘要: The effect of the addition N omega-nitro-L-arginine (L-NNA, 10 and 100 microM) to isolated rat kidneys perfused with a complex medium containing 21 amino acids has been studied. A cyclooxygenase inhibitor was added throughout block prostaglandin synthesis. L-NNA caused significant reductions in renal perfusion flow rate (PFR, 9.8 +/- 1.4 vs. 15.9 1.1 ml.min-1.g kidney wt-1, P less than 0.0001), glomerular filtration (GFR, 566 57 705 47 microliters.min-1.g 0.05) an increase relative fraction (%FF, 7.0 0.6 5.2 0.4%, compared control kidneys. had lower absolute sodium (72 9 88 4 mumol.min-1.g glucose reabsorption (3.5 0.5 5.4 0.4 0.05), corresponding mainly filtration. However, presence attenuated, too (82.8 2.0 87.0 3.3% 0.05 91.3 94.1 0.5%, 0.05). Potassium handling protein excretion were not changed significantly; fractional increased slightly L-arginine (47 5 55 7 ng.microliters-1, differences between treated (with exception FRGluc) could be fully or partially (L-NNA microns) reversed by adding (1 mM) medium. observed results obtained two different strains (Sprague-Dawley Wistar). Only changes, while D-NNA D-arginine without effect. It is concluded that NO/EDRF basally released from kidney, importance only regulation hemodynamics but also tubular function.