Antioxidative effects of adrenomedullin and vascular endothelial growth factor on lung injury induced by skeletal muscle ischemia-reperfusion.

Purpose: The aim of this study was to investigate the effects of adrenomedullin (AM) and vascular endothelial growth factor (VEGF) on lung injury as a remote organ following skeletal muscle ischemia-reperfusion injury in a rat model.

Materials And Methods: Thirty-six Wistar rats were randomized into six groups (n=6). Laparotomy was performed in all groups under general anesthesia. Nothing else was done in Group S (Sham). Ischemia reperfusion group (Group I/R) underwent ischemia and reperfusion performed by clamping and declamping of the infrarenal abdominal aorta for 120 minutes, respectively. Group VEGF and Group AM received intravenous infusion of VEGF (0.8 μg/kg) or AM (12 μg /kg) respectively, without ischemia and reperfusion. Group IR+VEGF and Group IR+AM received intravenous infusion of VEGF (0.8 μg/kg) or AM (12 μg /kg) respectively immediately after 2 hours period of ischemia. At the end of reperfusion period. Lung tissue samples were taken for biochemical examination. Total oxidant status (TOS) and total antioxidant status (TAS) levels in lung tissue were determined by using a novel automated method. p<0.05 was considered as statistically significant.

Results: TOS levels were significantly higher in Group I/R, when compared with groups S, AM and VEGF (p=0.004, p=0.011, p=0.017, respectively) and significantly lower in groups I/R+AM and I/R+VEGF, when compared with Group I/R (p=0.018, p=0.006, respectively). TAS levels were significantly higher in Group I/R, when compared with groups S, AM and VEGF (p=0.006 p=0.016, p=0.016, respectively) and significantly lower in Group I/R+AM, when compared with Group I/R (p=0.016).

Conclusion: These findings indicate that AM and VEGF acted effectively on the prevention of lung injury induced by skeletal muscle ischemia-reperfusion injury in a rat model (Fig. 2, Ref. 30).