RT Journal Article SR Electronic T1 Endothelial Nitric Oxide Contributes to the Renal Protective Effects of Ischemic Preconditioning JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 153 OP 159 DO 10.1124/jpet.104.074427 VO 312 IS 1 A1 Hiroshi Yamasowa A1 Satoko Shimizu A1 Takao Inoue A1 Masanori Takaoka A1 Yasuo Matsumura YR 2005 UL http://jpet.aspetjournals.org/content/312/1/153.abstract AB We determined whether endothelial nitric oxide synthase (eNOS) plays an important role in the renal protective effect of ischemic preconditioning (IP) against the ischemia/reperfusion-induced acute renal failure (ARF) by using eNOS-deficient (eNOS-/-) and wild-type (eNOS+/+) mice. Ischemic ARF was induced by occlusion of the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after contralateral nephrectomy. IP, which consists of three cycles of 2-min ischemia followed by 5-min reperfusion, was performed prior to 45-min ischemia. In eNOS+/+ mice, IP treatment markedly attenuated the ischemia/reperfusion-induced renal dysfunction and significantly improved histological renal damage such as tubular necrosis, proteinaceous casts in tubuli, and medullary congestion. Constitutive nitric oxide synthase activity in the kidney without IP was markedly decreased 6 h after reperfusion, but this decreased response was not observed in eNOS+/+ mice with IP treatment. The improvement of renal dysfunction in eNOS+/+ mice with IP treatment was abolished by pretreatment with NG-nitro-l-arginine, a nonselective NOS inhibitor, whereas aminoguanidine, an inducible NOS inhibitor, had no effect. Finally, no protective effects of IP on ischemia/reperfusion-induced renal dysfunction and histological damage were observed in eNOS-/- mice. These findings strongly support the view that eNOS-mediated NO production plays a pivotal role in the protective effect of IP on ischemia/reperfusion-induced ARF. The American Society for Pharmacology and Experimental Therapeutics