Background: Renal ischemia-reperfusion (RIR) is an important etiopathological mechanism of acute renal failure (ARF).Erythropoietin (EPO) has been candidate as a nephroprotectant agent. However, its nephroprotective effect when it is accompanied with estrogen has not been studied in female.
Methods: Fifty six female rats were divided into seven groups. Each formed of 8 rats. Group I: control group. Group II: Female rats exposed to RIR (named RIR group).Group III: Female rats exposed to RIR and pretreated with EPO (named RIR+EPO group). Group IV: ovariectomized rats exposed to RIR (named OVR+RIR group). Group V: ovariectomized rats received estrogen (E) then exposed to RIR (named OVR+RIR+E group). Group VI: ovariectomized rats received EPO before RIR (named OVR+RIR+EPO group). Group VII: ovariectomized rats received E then received EPO before RIR (named OVR+RIR+E+EPO group).Serum creatinine, blood urea nitrogen (BUN) and renal blood flow (RBF) were measured. Tumor necrosis factor-α (TNF- α), Myeloperoxidase activity (MPO), nitric oxide (NO), endothelin-1(ET-1) and EPO levels were assessed in the renal tissue. Histopathology was assessed to detect renal damage score.
Results: RIR significantly increased the serum levels of creatinine and BUN with decrease in RBF. In addition it significantly increased TNF- α, MPO and endothelin-1 levels with decrease in NO and EPO levels in renal tissue. However, these parameters significantly reversed by EPO except RBF. Combination of E and EPO leads to significant decrease in the protective effect of EPO.
Conclusion: It seems that EPO could protect the kidney against RIR, while this protective effect was decreased when E was supplemented