局部注射5-氮胞苷修复猪心肌梗死后的心肌损伤

目的探讨5-氮胞苷局部注入猪急性心肌梗死（AMI）区后对心肌损伤的修复作用。方法幼猪20只,开胸结扎冠状动脉前降支建立猪AMI模型;3周后治疗组（10只）通过局部注射将1mg/ml的5-氮胞苷溶液1ml注入梗死区及其周边;对照组（10只）予以等量的培养液接种;术后3周及7周分别行单光子发射计算机断层扫描（PET）检查;7周后处死所有动物,获取心肌标本,HE、免疫组化及2,3,5-氯化三苯基四氮唑（TTC）染色观察损伤心肌的转归。结果PET示治疗组7周时可见前壁、心尖部放射性分布较3周时密集;对照组7周与3周比较无明显差异。TTC染色治疗组梗死区面积及所占百分比显著小于对照组,（4.06±0.29）cm2vs（5.41±0.28）cm2;（16.34±0.89）vs（21.23±1.02）%,P〈0.001]。HE染色治疗组梗死区可见散在带横纹的肌肉组织,电镜下新生细胞之间未见闰盘连接;免疫组化染色这些细胞肌球蛋白重链β（β-MHC）、心脏肌钙蛋白Ⅰ（cTnⅠ）及连接蛋白43（Cx43）呈阳性。对照组梗死区为均匀一致的纤维疤痕组织。结论5-氮胞苷局部注入猪AMI区后可以诱导产生新的带横纹的肌细胞,修复心肌损伤。

Repair of Swine Infarcted Myocardium with 5-azacytidine Intramyocardial Injection

Objective To study swine infarcted myocardium repairment after 5-azacytidine intramyocardial injection.Methods Twenty young swines were divided into the treatment and control group randomly.The acute myocardial infarction(AMI)models were made by ligating the left anterior descending(LAD)as previously described.After 3 weeks,1 ml 5-azacytidine in 1 mg/ml concentration was intramyocardium injected into infarcted and border regions in the treatment group(n=10).In the control group(n=10),the same volume of cell...