慢性间歇性缺氧大鼠心房结构重构的研究

发布时间：2018-05-17 19:51

本文选题：慢性间歇性缺氧 + 心房结构重构　；参考：《天津医科大学》2017年硕士论文

【摘要】：目的:通过建立慢性间歇性缺氧(CIH)大鼠实验模型,观察心房肌组织的一般病理变化和心房纤维化的情况,以及心房肌组织细胞外信号调节激酶1/2、磷酸化细胞外信号调节激酶1/2和核转录因子kappa B的表达情况,探讨慢性间歇性缺氧对SD大鼠心房结构重构(ASR)的影响及其相关的纤维化信号传导通路。方法:选取12只Sprague-Dawley(SD)健康雄性大鼠,每只体重在250-300g之间,普通饲料适应性喂养1周后,随机分为对照组(CTL组)和慢性间歇性缺氧组(CIH组),其中CTL组4只大鼠,CIH组8只大鼠。CTL组普通饲料饲养,每日自由进食、饮水、活动,CIH组给予每日间歇缺氧5小时处理,连续间歇缺氧3周,建立慢性间歇性缺氧大鼠实验模型,CIH组每日除间歇缺氧5小时外,其余时间同CTL组一样正常饲养。实验期间观察对比两组大鼠的精神、进食、饮水等一般情况。3周实验结束后,所有大鼠经腹腔注射麻醉后打开胸腔,分离暴露心脏,分别剪取左、右心房肌组织,将组织固定于4%的甲醛溶液中,梯度酒精脱水后制作石蜡切片,并进行组织病理学染色。HE染色法观察大鼠心房肌组织的一般病理变化;Masson染色法测量大鼠心房肌组织胶原容积分数,评价大鼠心房肌组织胶原纤维增生情况;免疫组织化学染色法检测大鼠心房肌组织细胞外信号调节激酶1/2(ERK1/2)、磷酸化细胞外信号调节激酶1/2(p-ERK1/2)和核转录因子kappa B(NF-κB)的蛋白表达水平并半定量分析,观察ERK信号传导通路和NF-κB信号传导通路的变化。结果:1.HE染色结果显示,与CTL组比较,CIH组大鼠心房肌组织细胞核大小不均,排列紊乱,心肌间隙增大。2.Masson染色结果显示CIH组较CTL组大鼠心房肌组织间隙增大,心肌间质纤维增生明显,心房纤维化程度高。3.免疫组织化学染色结果显示,CTL组和CIH组大鼠心房肌组织中ERK1/2、p-ERK1/2和NF-κB均有阳性表达,但与CTL组相比,CIH组大鼠心房肌组织ERK1/2蛋白表达水平升高,p-ERK1/2蛋白表达增加,p-ERK1/2/ERK1/2蛋白比值升高;NF-κB的表达增加。结论:1.慢性间歇性缺氧可引起大鼠心房肌组织细胞结构紊乱,心房肌间质纤维化,发生心房结构重构。2.慢性间歇性缺氧可激活ERK和NF-κB信号传导通路,激活的ERK和NF-κB信号传导通路参与了慢性间歇性缺氧过程中心房纤维化的形成,但其具体机制有待进一步研究。
[Abstract]:Objective: to observe the general pathological changes of atrial muscle tissue and atrial fibrosis by establishing a rat model of chronic intermittent hypoxia. And the expression of extracellular signal-regulated kinase 1 / 2, phosphorylated extracellular signal-regulated kinase 1 / 2 and nuclear transcription factor kappa B in atrial muscle, To investigate the effect of chronic intermittent hypoxia on atrial structural remodeling (ASR) and its related fibrosis signal transduction pathway in SD rats. Methods: twelve healthy male Sprague-Dawley (SD) rats, each weighing between 250 g and 300 g, were fed with normal diet for 1 week. The rats were randomly divided into two groups: control group (CTL group) and chronic intermittent hypoxia group (CBI group). Among them, 8 rats in CTL group were fed with normal diet, fed freely daily, drank water, and were treated with intermittent hypoxia for 5 hours per day. The experimental model of chronic intermittent hypoxia was established in rats with intermittent hypoxia for 3 weeks, except intermittent hypoxia for 5 hours per day, and the rest time was as normal as that in CTL group. During the experiment, the mental, eating and drinking conditions of the rats in the two groups were observed and compared. At the end of the experiment, all the rats were anesthetized by intraperitoneal injection to open the chest cavity, separate and expose the heart, and cut off the left and right atrial muscle tissues, respectively. The tissue was immobilized in 4% formaldehyde solution, and then the gradient alcohol was dehydrated to make paraffin sections. Histopathological staining and HE staining were used to observe the general pathological changes of rat atrial muscle tissue. Masson staining method was used to measure the collagen volume fraction of rat atrial muscle tissue and evaluate the proliferation of collagen fiber in rat atrial muscle tissue. The expressions of extracellular signal-regulated kinase 1 / 2 ERK1 / 2, phosphorylated extracellular signal-regulated kinase 1 / 2p-ERK1 / 2 and nuclear transcription factor kappa BNF- 魏 B were detected and semi-quantitatively analyzed by immunohistochemical staining. The changes of ERK signaling pathway and NF- 魏 B signaling pathway were observed. Results 1. The results of he staining showed that compared with the CTL group, the nuclei of the atrial myocytes in the CIH group were unevenly sized and disordered, and the myocardial gap was enlarged. 2. The results of Masson staining showed that the gap between the atrial myocytes of the CIH group and the CTL group was larger than that of the CTL group. Myocardial interstitial fiber proliferation is obvious, atrial fibrosis is high. 3. 3. The results of immunohistochemical staining showed that ERK1 / 2 p-ERK1 / 2 and NF- 魏 B were positive in rat atrial myocytes in CTL group and CIH group. However, compared with CTL group, the expression level of ERK1/2 protein in atrial muscle was increased and the ratio of p-ERK1 / 2 / ERK1 / 2 protein was increased, and the expression of NF- 魏 B was increased. Conclusion 1. Chronic intermittent hypoxia can lead to atrial tissue structure disorder, atrial interstitial fibrosis, atrial structural remodeling. 2. Chronic intermittent hypoxia can activate ERK and NF- 魏 B signal transduction pathway. Activated ERK and NF- 魏 B signal transduction pathway participate in the formation of atrial fibrosis during chronic intermittent hypoxia, but its specific mechanism needs further study.
【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R541.75

【参考文献】