RESUMEN
BACKGROUND: Ischemic acute renal failure (ARF) is increasingly recognized as involving chronic functional and structural sequelae. Ischemia reperfusion injury (I/R) plays a major role in delayed graft function and long-term changes after kidney transplantation, also. The present study was designed to evaluate the long-term changes after acute ischemic injury and whether renoprotection by alpha-MSH in the acute ischemic stage, could reduce the long-term sequelae. METHODS: In control group, ischemia/reperfusion injury was induced in male Sprague-Dawley rats by clamping Lt. renal pedicle for 15, 45, 60 minutes after removal of Rt. Kidney and followed by reperfusion. The animals in alpha-MSH group were injected alpha-MSH prior to reperfusion and then every day for 1 week. We measured BUN, creatinine at 24 hour after I/R injury, and in each group, 6 animals were sacrified at 1 week and 4 weeks after I/R injury to evaluate apoptosis, ED1, PCNA, and histopathologic changes. RESULTS: At 4 weeks after I/R injury, the remnant structural damage such as apoptosis, ED1 stained cells, MT (+) tubulointerstitial fibrosis were observed. alpha-MSH could reduce the initial functional injury, and apoptosis, ED1 stained monocyte, MT (+) tubulointerstitial fibrosis, also. CONCLUSION: Renal function was recoverd at 4 weeks after I/R injury, but structural sequelae such as apoptosis, fibrosis were remnant. alpha-MSH could attenuate initial functional damage and remnant fibrosis.