【摘要】 目的探讨大鼠急性心肌梗死(AMI)后心功能变化和病理演变规律及其对心肌梗死干细胞移植治疗的影响。方法雄性Wistar大鼠40只随机分为假手术0周组(SH0周组,n=10)、MI 2周组(MI 2周组,n=10)、MI 4周组(MI 4周组,n=10)、MI 8周组(MI 8周组,n=10)。结扎冠状动脉左前降支制作大鼠急性MI模型,分别于术后观察期满,用超声评价心脏结构和左心导管检测血流动力学改变,并取心脏组织行HE染色,观察心肌病理改变。假手术组仅开胸并在左前降支下过线。结果MI2周后与假手术0周组相比,大鼠左心室舒张末压明显增高(LVEDP19.75±7.18mmHg vs 2.10±1.26mmHg,P<0.01),左心室内压力最大上升速率明显减慢(+dp/dtmax4.11±0.74mmHg/ms vs 6.20±0.70mmHg/ms,P<0.01),最大下降速率亦显著减慢(-dp/dtmax3.54±0.55mmHg/ms vs 5.82±0.54mmHg/ms,P<0.01)。MI4周时上述改变更明显,但MI8周时心功能未进一步恶化。超声见心脏结构变化与血流动力学改变相一致。HE染色观察梗死后12h梗死区弥漫的中性多形核细胞浸润,在2周时达到高峰,4周后基本消退。结论本研究显示大鼠梗死后其炎症反应高峰2周时出现,4周后基本完成梗死后修复过程,其演变规律可能对AMI干细胞治疗效果有影响。更多还原

【Abstract】 Objective To study the natural course of healing the infarction in rat model of myocardial infarction. Methods Forty male Wistar rats were randomized into four groups: sham group (SH 0 week n=10),MI two weeks group (MI 2 weeks n=10), MI four weeks group (MI 4weeks n=10) and MI eight weeks group (MI 8 weeks n=10).Acute MI were established by ligating the left anterior descending artery,Hemodynamics,ventricular remodeling parameters,and hematoxylin-eosin staining were investigated in the experimental animals respectively. Results In the rats with ligation for 2 weeks, Compared with the sham group,hemodynamic studies found a significantly increased left ventricular end- diastolic pressure (LVEDP 19.75 ± 7.18 mmHg vs 2.10 ± 1.26 mmHg,P <0.01),decrease of +dp/ dtmax(4.11 ± 0.74 mmHg/ms vs 6.20 ± 0.70 mmHg/ms,P <0.01), and - dp/dtmax(3.54 ± 0.55 mmHg/ms vs 5.82 ± 0.54 mmHg/ms,P <0.01).In the rats with ligation for 4 weeks, their heart function deteriorates forwardly,but there were no striking difference between MI 4 weeks group and MI 8 weeks group.In addition, Echocardiography demonstrated the same changes of ventricular remodeling parameters. Hematoxylin-eosin staining showed a great number of inflammatory cells infiltration around the infarct zone at 12 hours after ligation, the maximal inflammatory cells infiltration at 2 weeks and an elimination of inflammatory after 4 weeks of ligation. Conclusion The inflammatory reaction reaches its peak at 2 weeks after AMI, 4 weeks time is needed to complete the repairment of broken heart, and the rule probably plays a pivotal role in the stem cell therapy of AMI.更多还原