Methods: Twenty-four Wistar albino rats were randomized to three groups equal in number. Control rats underwent laparotomy and IAA dissection without IR. Two groups underwent aortic IR designed as 30 min of ischemia by clamping of the IAA with an atraumatic microvascular clamp, followed by 60 min of reperfusion after removal of the aortic clamp. In one aortic IR group, 1000 U/kg erythropoietin was administered subcutaneously 5 min before declamping of the IAA. The rats were decapitated under deep anesthesia and the lungs were removed. Tissue levels of malondialdehyde (MDA) and activity levels of superoxide dismutase (SOD), catalase, and glutathione peroxidase were measured and lung specimens were examined histopathologically.

Results: Rats treated with aortic IR alone had significantly higher tissue MDA levels and activity levels of SOD and catalase compared to the control group (p<0.05). Erythropoietinadministered rats exhibited significantly lower catalase activity than the aortic IR group (p<0.05). In histopathological examination, rats treated with aortic IR alone had significantly higher scores for alveolar congestion, inflammatory infiltration, intraalveolar hemorrhage, intraalveolar macrophages, and overall lung injury compared to the control rats (p<0.05). Erythropoietin-administered rats had lower scores in all these parameters compared to the aortic IR group, with scores of inflammatory infiltration, intraalveolar macrophages, and overall lung injury being significantly lower (p<0.05).

Conclusion: Erythropoietin attenuates the severity of lung injury occurring after abdominal aortic IR in rats.