小鼠动力性肺动脉高压肺组织TGF-β1及相关miRNAs表达变化的研究

发布时间：2018-01-22 05:24

本文关键词： 肺动脉高压 TGF-β1 miRNA-19a 小鼠肺动脉高压模型　出处：《西南医科大学》2017年硕士论文　论文类型：学位论文

【摘要】：目的:本研究通过小鼠动力性肺动脉高压模型探索肺组织TGF-β1及相关mi RNAs的表达与肺血管重构及肺动脉高压形成之间的关系,进而了解TGF-β1及相关mi RNAs的表达是否与肺动脉高压的进展快慢有相关性,从而提供早期诊断CHD-PAH(先天性心脏病相关肺动脉高压)的临床指标。方法:建立肺动脉高压小鼠模型,以模型小鼠肺组织为研究对象,进一步验证血流动力学的改变对肺组织TGF-β1及相关miRNAs表达的影响。方法如下:将20只雄性C57小鼠随机分成2组:A1,A2,其中A1为实验组,A2为假手术组。两组均采用戊巴比妥钠以40mg/kg腹腔麻醉。实验组左侧第3肋间开胸,切除左肺,假手术组左侧第3肋间开胸,不切除左肺。手术8周后处死,实验组、假手术组分别测右心室收缩压(RVSP)及称量右心室(RV)和左心室(LV)+室间隔(SP)的质量,计算右心肥厚指数(RVHI)(右心室和左心室+室间隔的比值)。实验组,假手术组的右肺分别进行HE染色后做病理切片,分析判断模型是否符合肺动脉高压的病理生理改变,用免疫组化检测TGF-β1在肺动脉的表达情况,qRT-PCR分别检测TGF-β1及相关miRNAs的表达量。结果:(1)与假手术组相比,实验组的RVSP为49.7±6.82mmhg,RVHI为0.347±0.04,假手术组的RVSP为20.3±4.53mmhg,RVHI为0.199±0.03(均为P0.01),实验组较假手术组RVSP及RVHI均明显升高。实验组肺组织切片镜下可见血管内皮层明显增生,微血管瘤形成,细小肺血管闭塞、机化,肺血管平滑肌层和内外弹力纤维层均明显增厚,中膜增厚,血管腔减小,肺动脉横切面积为3级,免疫组化检测TGF-β1蛋白表达显著高于假手术组(均为P0.05)。(2)在实验组动物模型肺组织中的TGF-β1的表达量为假手术组肺组织的1-3倍,实验组小鼠肺组织中miRNA-19a表达较假手术组增高15-30倍,miRNA-18a表达增高1-4倍,miRNA-23a表达1-2.5倍,miRNA-25a表达较假手术组增高1-3倍,(P均0.05)。其中实验组中miRNA-19a表达较其它miRNAs显著升高(P0.05)。结论:左肺切除造成的血流动力学变化可导致小鼠的肺动脉高压形成,这种肺动脉高压的动物模型可用于CHD-PAH的实验室研究。TGF-β1及miRNA-19a的高表达可能参与了小鼠肺动脉高压模型中肺血管的重塑及肺动脉高压的形成。
[Abstract]:Objective: to investigate the relationship between the expression of TGF- 尾 1 and related mi RNAs and pulmonary vascular remodeling and pulmonary hypertension in mice with dynamic pulmonary hypertension. To investigate whether the expression of TGF- 尾 1 and related mi RNAs is related to the rate of progression of pulmonary hypertension. Methods: the model of pulmonary hypertension in mice was established, and the lung tissue of the model mice was taken as the research object. The effects of hemodynamic changes on the expression of TGF- 尾 1 and related miRNAs in lung tissue were further verified. Methods: 20 male C57 mice were randomly divided into 2 groups: 1. Both groups were anesthetized by 40 mg / kg pentobarbital sodium. The left third intercostal thoracotomy was performed in the experimental group, left lung was excised, and the left third intercostal thoracotomy was performed in the sham operation group. The left lung was not resected. After 8 weeks of operation, the right ventricular systolic pressure (RV SPP), the right ventricular volume (RV) and the left ventricular (LVL) ventricular septum (SPV) were measured in the experimental group and the sham-operated group, respectively. The right ventricular hypertrophy index and the ratio of right ventricle to left ventricular septum were calculated. The expression of TGF- 尾 1 in pulmonary artery was detected by immunohistochemistry. QRT-PCR was used to detect the expression of TGF- 尾 1 and related miRNAs. Results compared with sham operation group, the RVSP of experimental group was 49.7 卤6.82 mmhg. RVHI was 0.347 卤0.04, RVSP in sham-operated group was 20.3 卤4.53mmg / g, RVSP was 0.199 卤0.03 (all P 0.01). RVSP and RVHI in the experimental group were significantly higher than those in the sham-operated group. In the experimental group, vascular endothelial layer proliferation, microangioma formation, small pulmonary vascular occlusion and organization could be seen in the lung tissue sections of the experimental group. The pulmonary vascular smooth muscle layer and the inner and outer elastic fiber layer were obviously thickened, the middle membrane thickened, the blood lumen decreased, and the transverse area of pulmonary artery was grade 3. The expression of TGF- 尾 1 protein by immunohistochemistry was significantly higher than that in sham-operated group (P 0.05, P < 0.05). The expression of TGF- 尾 1 in lung tissue of experimental group was 1-3 times as much as that of sham operation group. The expression of miRNA-19a in lung tissue of experimental group was 15-30 times higher than that of sham-operated group. The expression of miRNA-18a was 1-4 times higher than that of sham-operated group, and the expression of miRNA-23a was 1-2.5 times higher than that of sham operation group. The expression of miRNA-25a was 1-3 times higher than that of sham operation group. The expression of miRNA-19a in the experimental group was significantly higher than that in other miRNAs groups (P 0.05). Conclusion: hemodynamic changes caused by left lung resection may lead to pulmonary hypertension in mice. The high expression of TGF- 尾 1 and miRNA-19a may be involved in pulmonary vascular remodeling in mice with pulmonary hypertension. And the formation of pulmonary hypertension.
【学位授予单位】：西南医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R544.1

【参考文献】