Adrenomedullin attenuates aortic cross-clamping–induced myocardial injury in rats

Abstract Background In this study we investigate the effects of adrenomedullin on myocardial injury after ischemia-reperfusion (I/R) after abdominal aortic surgery. Methods Thirty-two Wistar rats were randomized into 4 groups (n = 8) as follows: control group (sham laparotomy), the aortic I/R group, aortic I/R plus adrenomedullin group (underwent aortic I/R periods, and received a bolus intravenous injection of .05 μg/kg/min adrenomedullin), and the control plus adrenomedullin group. Results Biochemical analysis showed that aortic I/R significantly increased ( P < .05) the plasma levels of troponin-I and tumor necrosis factor-α, and the myocardial tissue levels of malondialdehyde, superoxide dismutase, catalase, and angiotensin II, whereas aortic I/R plus adrenomedullin significantly decreased these same factors ( P < .05). Aortic I/R significantly increased ( P < .05) myocardial tissue levels of nitric oxide whereas aortic I/R plus adrenomedullin significantly increased the same factor ( P < .05). Conclusions These results indicate that adrenomedullin has protective effects against myocardial injury induced by abdominal aortic I/R in rats.