论文部分内容阅读
目的建立慢性肾衰竭诱发心室肥厚大鼠模型,为深入研究慢性肾衰竭患者并发心血管疾病的发病机制及防治措施提供实验基础。方法 20只250～300 g雄性SD大鼠按体重随机分成2组,慢性肾衰竭并发心室肥厚模型组和假手术组,其中慢性肾衰竭并发心室肥厚模型组10只动物背左侧或腹部切口充分暴露左侧肾脏,剥离肾包膜,迅速切除上、下极各约1/3。术后7 d进行第2次手术,右侧背部切开暴露右肾,结扎肾蒂,摘除右肾。假手术组10只动物除保留肾外,其他手术过程同样执行。选取存活动物作为观察对象,持续17周。实验结束后对大鼠进行心电图测定和心脏超声检查,测定左室长轴切面左室舒张末期内径(LVIDd),左室收缩末内径(LVIDs),左室舒张末期前壁厚度(LVAWd),左室收缩末期前壁厚度(LVAWs),左室舒张末期后壁厚度(LVPWd),左室收缩末期后壁厚度(LVPWs),左室射血分数(LVEF)、缩短分数(FS)和左室质量(LV Mass)。处死动物,取心脏称重,作病理分析和用电镜观察心脏超微结构。同时对心脏组织进行microRNA芯片分析。结果与假手术组相比:①模型大鼠心脏临床生化检测指标有明显改变,AST,LDH和CK等有明显的升高(P<0.05);②模型组大鼠心脏重量及脏器系数明显增加(P<0.05);③心电图结果显示模型组大鼠心脏有室性心动过速、缺血、缺氧和高血钾表现。④心脏彩超结果显示,模型组大鼠左室舒张末期后壁厚度(LVPWd)、左室舒张末期前壁厚度(LVAWd)和校正后的左室质量(LV Mass)有明显增加(P<0.05或P<0.01);⑤光镜结果显示,模型组大鼠心肌细胞变性坏死,断裂或破坏消失,间质增宽,炎症细胞灶性浸润,部分心肌细胞部分胞核肥大,呈胖卵圆形。⑥电镜结果显示,模型组大鼠部分线粒体轻微肿胀,有些线粒体脊紊乱,融合,甚至消失,有的线粒体腔内出现大而不规则的致密体。⑦基因芯片及PCR验证后显示,相比假手术组,模型组大鼠有3个microRNA表达增加。结论大鼠5/6肾脏切除17周后心脏出现明显的病理变化,较好的模拟了临床慢性肾衰竭患者发生心室肥厚的进程,可以为该疾病的防治提供较好的实验基础。
Objective To establish a rat model of ventricular hypertrophy induced by chronic renal failure and provide the experimental basis for further study on the pathogenesis and prevention of cardiovascular disease in patients with chronic renal failure. Methods Twenty male Sprague-Dawley rats weighing 250-300 g were randomly divided into 2 groups according to body weight. Chronic renal failure complicated by ventricular hypertrophy and sham-operation group, in which 10 rats with chronic renal failure complicated by ventricular hypertrophy were dorsal or abdominal incision Exposed the left kidney, peel the renal capsule, rapid removal of the upper and lower pole about 1/3. The second operation was performed on the 7th day after surgery. The right kidney was dissected and exposed to the right back. The renal pedicle was ligated and the right kidney was removed. In the sham operation group, 10 animals except the kidney remained the same. Survival animals were selected as the observation object for 17 weeks. At the end of the experiment, the left ventricular end-diastolic diameter (LVIDd), left ventricular end-systolic diameter (LVIDs), left ventricular end-diastolic anterior wall thickness (LVAWd) LVAWs, LVPWd, LVPWs, LVEF, FS, and left ventricular mass (LVEDs) (LV Mass). The animals were sacrificed and the heart was weighed for pathological analysis and electron microscopy to observe the ultrastructure of the heart. At the same time microRNA chip analysis of heart tissue. Results Compared with the sham-operated group, the indexes of clinical biochemistry in the model rat heart changed obviously, the levels of AST, LDH and CK were significantly increased (P <0.05); ② The heart weight and organ coefficient of the model group were significantly (P <0.05). ③The results of electrocardiogram showed ventricular tachycardia, ischemia, hypoxia and hyperkalemia in the model rats. ④ The results of echocardiography showed that left ventricular end-diastolic wall thickness (LVPWd), left ventricular end-diastolic anterior wall thickness (LVAWd) and corrected LV mass in model group were significantly increased (P <0.05 or P <0.01). ⑤The results of light microscopy showed that the myocardial cells of the model group were degenerated, necrotic, ruptured or destroyed, the interstitial broadened, the focal inflammatory cells were infiltrated, and some of the myocardial cells were enlarged in nuclei and fat oval. ⑥ Electron microscopy showed that some mitochondria in the model group were slightly swollen. Some mitochondrial ridges were disorganized, confused and even disappeared. Some large and irregular dense bodies appeared in some mitochondria. ⑦ gene chips and PCR validation showed that compared with sham operation group, the model group of rats increased expression of three microRNAs. Conclusion The pathological changes of the heart appeared in 5/6 kidneys 17 weeks after the resection in rats. The progress of ventricular hypertrophy in the patients with chronic renal failure was better simulated, which could provide a good experimental basis for the prevention and treatment of this disease.