色甘酸钠对大鼠心肌梗死后心肌凋亡及凋亡蛋白的影响

The Effects of Cromolyn Sodium on Myocardial Apoptosis and Apoptosis Protein after Myocardial Infarction

目的研究肥大细胞脱颗粒程度对心肌梗死后的心肌凋亡及心肌纤维化的影响,探讨细胞凋亡机制在心肌梗死后心室重构中的作用。方法建立雄性SD大鼠心肌梗死模型,分成假手术组(n=6)、模型组(n=8)、色甘酸钠组(n=7)。术后4周,留取心肌标本行TUNEL染色观察心肌细胞凋亡指数(AI),Masson染色检测心肌胶原容积分数(CVF),Western blot法检测Caspase-3、Bcl-2和Bax蛋白表达。结果与假手术组相比,模型组、色甘酸钠组在AI、CVF、Caspase-3及Bax蛋白表达量等方面均显著升高(P<0.05),Bcl-2蛋白表达明显下降;色甘酸钠组与模型组相比,AI、CVF、Caspase-3及Bax蛋白表达量均有所下降(P<0.05),Bcl-2蛋白有所升高,但两者差异无统计学意义(P=0.127)。AI与CVF呈正相关(r=0.769,P<0.01)。结论心肌梗死后心肌凋亡显著增加,抑制肥大细胞脱颗粒可明显减少心肌凋亡,减轻左心室心肌纤维化程度。

Aim To clarify the effects of myocardial apoptosis on ventricular remodeling after myocardial infarction, and to study the effects of mast cell degranulation on myocardial apoptosis and fibrosis. Methods Myocardial infarction （MI） model was established in male Sprague-Dawley （SD） rats by ligation of left anterior descending coronary artery. The rats were randomly divided into three groups： sham-operated group （ n = 6）, MI model group （n = 8） and cromolyn sodium group （ n = 7 ）. Four weeks after ligation, myocardial apoptosis index （ AI）, collagen volume fraction （CVF） and expression level of caspase-3, Bcl-2 and Bax were obtained. Results Compared with sham-operated group, AI, CVF and expression level of caspase-3 and Bax in MI model group and cromolyn sodium group increased （P〈0.05）, but decreased in Bcl-2 （P〈0.05）. Cromolyn sodium group was decreased in these factors （P〈0.05） compared with MI model group. Bcl-2 level in cromolyn sodium group was higher than MI model group, but there is no significant difference among these two groups （P=0.127）. The AI was positive correlation with CVF （r = 0.769, P〈0.01）. Conclusions Myocardial apoptosis increased after myocardial infarction. Mast cell degranulation inhibition can decrease apoptosis and reduced myocardial fibrosis.