过表达microRNA-21对心肌梗死面积大小的影响

发布时间：2018-11-11 13:02

【摘要】：目的：本研究探讨在老鼠心肌梗死当时，直接注入携带microRNA-21基因的腺病毒载体，实现过表达microRNA-21,通过过表达microRNA-21探讨其对心肌梗死面积大小的影响，为将来指导临床预防与治疗心肌梗死提供新的思路。方法：本研究选取40只体重在250-300g之间的雄性标准SD大鼠，随机分为四组，每组10只，分别为：携带microRNA-21基因的腺病毒载体组、空基因的腺病毒载体组、生理盐水组、假手术组。在相对无菌条件下按照标准心梗模型的操作规范，通过腹腔注射乌拉坦(0.4ml/100g)麻醉大鼠，待老鼠四肢疼痛感觉消失后，开始切开颈部皮肤，钝性分离颈部肌肉，找到气管，穿线，呈T字形剪开气管，插管连接呼吸机，在心电监护下，开胸结扎大鼠左心耳和肺动脉圆锥交界处下3-4mm的冠状动脉左前降支，观察心电图ST段抬高，远端心肌变苍白30后分钟，确定完成心肌梗死模型的建立，用微量注射器向心肌梗死周围三点注入携带microRNA-21基因腺病毒载体、空基因的腺病毒载体、生理盐水同等剂量100ul（病毒滴度为1.0×109pfu/只），假手术组穿线不结扎也不注入目标物质，关胸后向腹腔注入40万单位青霉素预防感染，再继续饲养大鼠3天，3天后脱臼处死大鼠，取出心脏，生理盐水冲洗，冰冻切片通过TTC染色检测心肌梗死面积大小；RT-qPCR检测心肌梗死周围组织microRNA-21基因的表达量，，然后将所得的数据进行统计学处理，得出结论。结果：注射携带microRNA-21腺病毒载体组较其他三组microRNA-21表达量明显增多（P0.01），其他三组之间无明显统计学差异；注射携带microRNA-21腺病毒载体组心肌梗死面积大小较其他组明显减少（P0.05），其他三组之间无明显统计学差异。结论：直接心肌内注射携带microRNA-21基因腺病毒载体可实现心肌内microRNA-21基因的过表达，该基因表达出的microRNA-21在心肌梗死3天后有减少心肌梗死面积大小的作用，具体机制尚待进一步研究证实。
[Abstract]:Objective: to investigate the effect of overexpression of microRNA-21, on myocardial infarction size by directly injecting adenovirus vector carrying microRNA-21 gene during myocardial infarction in rats. To provide new ideas for clinical prevention and treatment of myocardial infarction in the future. Methods: forty male standard SD rats weighing 250-300g were randomly divided into four groups: adenovirus vector group carrying microRNA-21 gene, adenovirus vector group with empty gene, normal saline group. Sham-operation group. Under the condition of relative sterility, the anesthetized rats were anesthetized by intraperitoneal injection of 0.4ml/100g according to the standard myocardial infarction model. After the pain in the limbs disappeared, the skin of the neck was cut open and the muscles of the neck were obtuse. Trachea was found, perforated, trachea was cut in T shape, intubation was connected to ventilator, left anterior descending branch of coronary artery of 3-4mm was ligated under ECG monitoring, left atrial appendage and pulmonary artery conical junction were ligated in rats, and ST segment elevation of ECG was observed. After 30 minutes of palliation of the distal myocardium, the establishment of myocardial infarction model was determined. The adenovirus vector carrying microRNA-21 gene and the adenovirus vector carrying empty gene were injected into the myocardium around myocardial infarction with micro syringe at three points. The same dose of normal saline 100ul (virus titer was 1.0 脳 109pfu/), the sham operation group did not ligate or inject target material, after closing the chest, 400000 units penicillin was injected intraperitoneally to prevent infection, and then the rats were kept for 3 days. Three days later, the rats were killed by dislocation, the heart was taken out, the size of myocardial infarction was detected by TTC staining. RT-qPCR was used to detect the expression of microRNA-21 gene in the tissue around myocardial infarction. Results: compared with the other three groups, the microRNA-21 expression in the adenovirus carrying microRNA-21 group was significantly increased (P0.01), but there was no significant difference among the other three groups. The size of myocardial infarction in the adenovirus carrying microRNA-21 group was significantly smaller than that in the other groups (P0.05), but there was no significant difference among the other three groups. Conclusion: direct intramyocardial injection of adenovirus vector carrying microRNA-21 gene can realize the overexpression of microRNA-21 gene in myocardium. The microRNA-21 expressed by this gene can reduce the size of myocardial infarction 3 days after myocardial infarction. The specific mechanism needs further study and confirmation.
【学位授予单位】：皖南医学院
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R542.22

【相似文献】