肾上腺素致大鼠应激性心肌损伤性别差异研究

摘要

Objective To investigate the gender difference in the incidence of stress cardiomyopathy ( SCM ) in rats.Methods Female and male rats were intravenously injected with different doses of epinephrine (Epi).Then they were assessed for their survival , lung coefficient, the levels of brain natriuretic peptide (BNP) and stimulating G protein ( Gαs ) in the apex of the heart .Results The male rats produced an obviously lower survival rate than the female after injected with 1.71 ×10 -7 and 2.57 ×10 -7 mol/100 g of Epi (P<0.05 or P<0.01).The levels of serum BNP were significantly higher in the male rats exposed to 8.56 ×10 -8 mol/100 g of Epi, but lower in those receiving either 1.71 × 10 -7 or 2.57 ×10 -7 mol/100 g of Epi, when compared with the female (P<0.01).Remarkable increases were seen in the male group than the female as to lung coefficient after injection of 1.71 ×10 -7 , 2.57 ×10 -7 or 8.56 ×10 -8 mol/100 g of Epi (P<0.01), while no statistical difference was found as to the expression of Gαs protein between both groups (P>0.05).Conclusion With the increase of epinephrine dose , the resultant myocardial damage becomes gradually seve-rer in male than female rats .Given the same stress , female rates may present reversible heart failure , while the heart fail-ure in male rats may be fatal , which then explain the gender difference in the incidence of SCM .%目的：初步探讨应激性心肌病（stress cardiomyopathy，SCM）发病率性别差异的原因。方法经颈静脉注射不同剂量的肾上腺素（epinephrine， Epi），观察各组雌雄大鼠的存活情况、脑尿钠肽（brain natriuretic peptide， BNP）水平、肺系数及心尖部兴奋性G蛋白（ Gαs ）的表达含量。结果雄鼠Epi 1．71×10－7、2．57×10－7 mol／100 g剂量组的存活率明显低于雌鼠（P＜0．05或P＜0．01）；雄鼠Epi 8．56×10－8 mol／100 g剂量组血清BNP的水平高于雌鼠（P＜0．01），在Epi 1．71×10－7、2．57×10－7 mol／100 g剂量组则低于雌鼠（P＜0．01）；雄鼠Epi 8．56× 10－8、1．71×10－7和2．57×10－7 mol／100 g 3个剂量组肺系数均高于雌鼠（P＜0．01）；各组雌雄大鼠心尖部Gαs 蛋白表达无明显差异（P＞0．05）。结论随着肾上腺素剂量的增加，雄鼠较雌鼠心肌损伤严重程度的差异更加明显，相同的应激情况下，雌鼠有可能表现为可逆性的心衰，而雄鼠则可能为致命性的心衰，从而造成了SCM发病率的性别差异。