摘要: |
目的 对急性心肌梗死(myocardial infarction,MI)大鼠进行双侧肾交感神经切除,探讨去肾交感神经术(renal sympathetic denervation,RDN)能否缓解MI后心室重构并进行可能的机制探讨。方法 结扎大鼠左冠状动脉前降支构建MI模型,实验分组为:MI组(n=10)、MI+RDN组(MI建模1周后进行RDN,n=10)和假手术组(n=10)。MI建模4周后对各组大鼠进行超声心动图检查测定心室重构程度和左心功能,对梗死边缘区心肌进行Masson染色观察心肌纤维化程度,免疫组化检测Ⅰ型胶原、Ⅲ型胶原和转化生长因子 β1(transforming growth factor β1,TGF-β1)的表达。结果 与MI组相比,MI+RDN组的左室射血分数(ejection fraction,EF)和短轴缩短率(fractional shortening,FS)升高,左室收缩末期内径(left ventricular internal dimensions at end systole,LLüIDS)和左室舒张末期内径(left ventricular internal dimensions at end diastole,LLüIDD)减少(P均<0.05)。心肌Masson染色结果显示,MI+RDN组大鼠梗死边缘区的心肌纤维化程度较MI组减轻。免疫组化检测显示,与MI组相比,MI+RDN组大鼠梗死边缘区的Ⅰ型胶原、Ⅲ型胶原和TGF-β1表达减少(P均<0.05)。结论 RDN可以改善MI大鼠心室重构,提高左心收缩功能,其机制可能与局部下调心肌TGF-β1表达进而减少Ⅰ型胶原和Ⅲ型胶原沉积有关。 |
关键词: 心肌梗死 心室重构 纤维化 去肾交感神经 |
DOI:10.3724/SP.J.1008.2014.00356 |
投稿时间:2013-11-22修订日期:2014-01-23 |
基金项目:第二军医大学长海医院“1255计划”项目(CH125542700). |
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Effects of renal sympathetic denervation on cardiac remodeling following myocardial infarction in rats |
LIU Su-xuan,WANG Guo-kun,DING Xue-yan,DONG Fei-fei,AN Li-na,ZHAO Xian-xian,QIN Yong-wen |
(Department of Cardiovasology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China *Corresponding author.) |
Abstract: |
Objective To explore the effect of renal sympathetic denervation (RDN) on cardiac remodeling in myocardial infarction (MI) rats and to investigate the related mechanism. Methods MI rats were induced by ligation of the anterior descending coronary artery. A total of 30 Wistar rats were randomly assigned to MI group (n=10), MI+RDN group (rats with RDN one week after MI, n=10), and Sham group (n=10). Four weeks after modeling, the left ventricular cardiac remodeling and function of rats were examined by echocardiography; the cardiac tissues in the infarct border zone were stained with Masson trichrome for fibrotic analysis. Protein expressions of collagen Ⅰ, collagens Ⅲ and transforming growth factor β1 (TGF-β1) were evaluated by immunohistochemistry. Results Compared with the MI group, the MI+RDN group had significantly increased ejection fraction (EF) and fractional shortening (FS) and significantly decreased left ventricular internal dimensions at end systole and end diastole (all P<0.05). The results of Masson staining showed that RDN after MI attenuated the collagen deposition around the border area of the infarct region. RDN treatment also inhibited the protein expression of collagenⅠ, Ⅲ and TGF-β1 in the border area of MI rats (P<0.05). Conclusion RDN treatment can attenuate cardiac remodeling and improve left ventricular function after MI, which might be associated with the inhibition of myocardial TGF-β1 expression and the subsequent suppression of collagen deposition. |
Key words: myocardial infarction ventricular remodeling fibrosis renal sympathetic denervation |