Nitric oxide and prostanoids protect the renal outer medulla from radiocontrast toxicity in the rat.

摘要: Human radiocontrast nephrotoxicity is predicted by the presence of multiple risk factors, often associated with compromised renal circulation. To produce a simple model nephropathy, rats were pretreated indomethacin and N omega-nitro-L-arginine methyl ester (L-NAME, to inhibit nitric oxide synthesis) before administration iothalamate. Acute failure consistently developed, decline in creatinine clearance from 1.05 +/- 0.10 0.27 0.05 ml/min (P < 0.001) selective necrosis 49 9% medullary thick ascending limbs. Hemodynamic studies using laser-Doppler probes revealed that when injected alone, iothalamate increased outer blood flow 196 25% baseline 0.001). Pretreatment L-NAME or both reduced basal transformed vasodilator response into vasoconstriction, prolonged reduction less then half baseline. Combined indomethacin, L-NAME, lowered 12 4% We conclude prostanoids have an important protective role material. Reduced synthesis these vasoactive substances renal/vascular diseases may predispose patients nephropathy.