论文部分内容阅读
目的探讨Ⅰ、Ⅲ型胶原在肥厚心肌组织中的变化特征。方法 SD大鼠60只,分为对照组和实验组,两组分别再分为1、4、8周组,每组10只。对照组背部皮下注射生理盐水4ml/(kg.d);实验组背部皮下注射异丙肾上腺素4mg/(kg.d)。两组分别注射1、4、8周,然后测定各组大鼠体重(BW)、心脏湿重(HW)、左室湿重(LVW),计算出HW/BW、LVW/BW;心肌组织冷冻切片,利用图像分析软件,测量心肌细胞横径(TDM)和心肌细胞截面积(CA)。免疫组织化学法检测各组心肌组织Ⅰ、Ⅲ型胶原的表达。Western blotting方法检测心肌肥厚大鼠心肌Ⅰ、Ⅲ型胶原蛋白表达及其含量。结果免疫组织化学结果显示,注射异丙肾上腺素1周后,Ⅰ和Ⅲ型胶原蛋白表达明显增加,4周后有所下降。Western blotting结果显示,实验各组Ⅰ型和Ⅲ型胶原蛋白表达均多于对照组(P<0.01);实验1周时Ⅰ型和Ⅲ型胶原蛋白表达量最高,4周和8周均下降。实验4周和8周组与1周组比较差异有统计学意义(P<0.05)。结论心肌肥厚发生1周左右是Ⅰ、Ⅲ型胶原增加的高峰期,以后趋于稳定。心肌肥厚主要引起胶原量的变化,不破坏胶原纤维的网络结构。
Objective To investigate the changes of type Ⅰ and type Ⅲ collagen in hypertrophic myocardium. Methods Sixty Sprague-Dawley rats were divided into control group and experimental group. The two groups were subdivided into 1, 4 and 8 week groups, 10 in each. The control group was subcutaneously injected with saline 4ml / (kg · d) subcutaneously. The experimental group was subcutaneously injected isoproterenol 4mg / (kg · d) subcutaneously. The rats in each group were injected for 1, 4, 8 weeks, then the body weight (BW), heart wet weight (HW) and left ventricular wet weight (LVW) were measured to calculate the HW / BW and LVW / Slides were taken and the cardiomyocyte diameter (TDM) and cardiomyocyte cross-sectional area (CA) were measured using image analysis software. Immunohistochemistry was used to detect the expression of collagen type Ⅰ and Ⅲ in each group. Western blotting was used to detect the expression of collagen type Ⅰ and Ⅲ and its content in cardiac hypertrophy of rats. Results Immunohistochemistry results showed that the expression of collagen type Ⅰ and Ⅲ increased significantly after isoproterenol injection for 1 week, and decreased after 4 weeks. The results of Western blotting showed that the expression of type I and type III collagen in experimental group was higher than that in control group (P <0.01). The expression of type I and type III collagen was highest at 1 week and decreased at 4 and 8 weeks. There was significant difference between the 4th week and the 8th week in the experimental group and the 1st week (P <0.05). Conclusions Cardiac hypertrophy occurs about 1 week and is the peak of increase of type I and type III collagen, and tends to be stable afterwards. Cardiac hypertrophy mainly causes changes in the amount of collagen, does not destroy the network structure of collagen fibers.