【作者】 向阳；

【导师】 马依彤；

【作者基本信息】 新疆医科大学 ， 心血管内科学， 2007， 硕士

【摘要】 目的:探讨性别对小鼠急性心肌梗死(AMI)后心脏破裂及早期左室重构的影响及分子机制。方法:不同性别C57BL小鼠,随机分入假手术组、心肌梗死(MI)组。建立AMI模型后,观察不同性别组小鼠心脏破裂发生率,并于AMI后第7天行超声心动图和血流动力学检查:应用酶谱法、病理组织学染色方法,分别于AMI后第3、7天检测基质金属蛋白酶(MMP-2,MMP-9)活性表达,炎性细胞浸润程度及心肌间质胶原含量的变化。结果:1)AMI后雄性组心脏破裂发生率显著高于雌性组(26.7%与7.0%,P＜0.05);2)与雌性组比较,雄性组AMI后第3天炎性细胞浸润程度明显增加(P＜0.05),第3、7天MMP-9表达增加,心肌间质胶原含量较低;3)AMI后第7天时,雄性假手术组平均动脉压(MAP)、左室收缩压(LVSP)均高于雌性组(P均＜0.05),雄性MI组较雌性MI组表现出显著的左室扩张、梗死区变薄、心功能障碍以及血流动力学恶化。结论:小鼠AMI后心脏破裂发生率存在性别差异,雄性明显高于雌性。炎性细胞浸润程度增加、MMP-9活性增高、原有间质胶原过度降解和左室早期重构恶化可能是雄性小鼠心脏破裂发生率增加的重要原因。更多还原

【Abstract】 Objective:To investigate gender differences in post-infarct cardiac rapture and early left ventricular remodeling in a mouse model and possible mechanisms.Methods:C57BL mice in two groups:males and females were divided into sham operation group and myocardial infarction(MI)group randomly.Following acute myocardial infarction(AMI) induced by open-chest surgery,the events of cardiac rupture were monitored,the echocar-diography and hemodynamics were performed at 7 days after surgery.Zymography and pathological staining were used to measure the activity of matrix metalloproteinases (MMPs),content of collagen and quantitate the inflammatory cells at 3 and 7 days after surgery.Results:1)A significantly higher incidence of cardiac rupture was observed in males than in females(26.7%versus 7.0%,P＜0.05).2)Males had a significantly higher number of inflammatory cells infiltrating at the infarct border at 3 days after surgery (P＜0.05).MMP-9 activity were higher in males than in females at 3 and 7 days after AMI. The collagen content were increased in females than in males after AMI.3)The MAP and LVSP in sham operation group were higher in male mice compared to female mice(both P＜0.05).And the severe infarct expansion,worse left ventricular(LV)remodeling and hemodynamics were showed in males compared to females at 7 days after surgery. Conclusion:The cardiac rupture rate during the first week after MI was significantly higher in male mice than in female mice.The mechanisms responsible for this gender-related difference in cardiac rapture were related to more infiltrating inflammatory cells,increased MMP-9 activity,premature collagen degradation,and aggravated early LV remodeling.更多还原