Role of endothelium-derived nitric oxide endothelin balance in contrast medium-induced acute renal vasoconstriction in dogs

Rationale and Objectives. The authors evaluated the involvement of nitric oxide and endothelin in radiographic contrast medium-induced changes in renal hemodynamics. Methods. Eleven anesthetized healthy dogs were each studied during three periods. Thirty minutes before the first, second, and third periods, the dogs received I mt per kilogram of body weight of isotonic saline, L-N-nitro-L-arginine-methyl-ester (L-Name, 10 mg/kg intravenously), and L-arginine (500 mg/kg intravenously), respectively. Renal blood how (RBF) and mean arterial blood pressure were continuously monitored. The glomerular filtration rate (GFR) was evaluated by means of polyfructosan clearance. Results. Contrast medium induced a significant (P < .05) decrease in RBF and GFR and a significant (P < .05) increase in urinary endothelin excretion, L-Name enhanced the effect of contrast media on RBF and GFR. L-arginine attenuated the effect of L-Name on the contrast medium-induced reduction of GFR. Conclusion. These findings support the hypothesis that acute contrast medium-induced intrarenal vasoconstriction map involve an imbalance of endothelial vasoactive agents, nitric oxide, and endothelin, and they confirm the involvement of hemodynamic changes in contrast medium-induced nephropathy.