Protective effects of erythropoietin on ischemia/reperfusion injury of rat ovary.

OBJECTIVES

To evaluate the effects of erythropoietin (EPO) as an antioxidant and tissue protective agent and study the biochemical and histopathological changes in experimental ischemia and ischemia/reperfusion (I/R) injury in rat ovaries.

STUDY DESIGN

36 Adult female rats were used. The experimental groups were designed as Group 1: sham operation; Group 2: bilateral ovarian ischemia; and Group 3: 3 h period of ischemia followed by 3 h reperfusion. Group 4 rats were administered a 5000 IU dose of EPO, before 0.5 h of ischemia, and then bilateral ovarian ischemia was applied. After a 3 h period of ischemia, the bilateral ovaries were removed. In Group 5, a 3 h period of bilateral ovarian ischemia was applied. 2.5 h after the induction of ischemia, the rats were administered the same dose of EPO. At the end of a 3 h period of ischemia, 3h reperfusion was continued after the ovaries were removed. Group 6 underwent a sham operation after administration of 5000 IU/kg of EPO. After the experiments, superoxide dismutase (SOD), inducible nitric oxide synthase (iNOS), and myeloperoxidase (MPO) activity were determined, and histopathological changes were examined in all rat ovarian tissue.

RESULTS

Ischemia and ischemia/reperfusion increased the iNOS and MPO activity while decreasing the SOD activity significantly in comparison to the sham group. The 5000 IU/kg of EPO before ischemia and I/R reversed the trend in iNOS and MPO activities. The levels of SOD were decreased by the ischemia and I/R. The administration of EPO before ischemia and I/R treatments also reversed the trend in the SOD levels. In the ischemia/reperfusion plus EPO groups, though we observed minimal vascular dilation in the ovary stroma and some degenerative cell clusters, most of cellular structures did not show any pathological changes.

CONCLUSIONS

Administration of EPO is effective in reversing tissue damage induced by ischemia and/or ischemia/reperfusion in ovaries.