糖尿病仓鼠心肌chymase mRNA表达增强  

Expression increase of chymase gene in diabetic hamsters

作　　者：赵柯湘[1] 肖谦[1] 黄昶荃[1] 高原[1] 

机构地区：[1]重庆医科大学第一附属医院老年病科,重庆400016

出　　处：《基础医学与临床》2007年第9期985-990,共6页Basic and Clinical Medicine

基　　金：重庆市自然科学基金(2005BB5274)

摘　　要：目的观察chymase mRNA表达与糖尿病仓鼠心肌局部血管紧张素Ⅱ(AngⅡ)水平以及心肌病变的关系。方法腹腔注射链脲菌素(STZ)诱导1型糖尿病仓鼠模型,18周时电镜观察心肌超微结构,SABC法检测心肌Ⅰ、Ⅲ型胶原水平,TUNEL技术检测心肌细胞凋亡,RT-PCR检测chymase mRNA表达水平,放射免疫分析法测定心肌AngⅡ含量。结果糖尿病组仓鼠血糖、血脂明显升高,心肌细胞线粒体肿胀明显、局部破裂,肌丝广泛溶解,核肿胀,Ⅰ、Ⅲ型胶原沉积、心肌细胞凋亡明显。心肌AngⅡ含量,心肌chyamse mRNA表达水平均显著高于对照组(P<0.01)。结论存在糖尿病心肌病变的仓鼠心肌中,chymase mRNA表达水平以及AngⅡ含量显著升高,可能是导致心肌Ⅰ、Ⅲ型胶原沉积、心肌细胞凋亡等心肌病变的重要原因。Objective To explore how does chymase affect diabetic cardiomyopathy by investigating the gene expression of chymase and the relationship between the gene expression of chymase and the angiotensin Ⅱ in the cardiomyopathy of streptozotocin-induced diabetic hamasters. Methods Diabetic hamsters were induced by intraperitoneal injection of STZ 40 mg/kg once a day for 3 days. After stabilization of diabetic state for 18 weeks, the myocardial uhrastructure was observed with electron microscope and pathologic changes were observed by light microscopy. Immunohistochemistry was used to measure the level of expression of type Ⅰ and type Ⅲ collagen in diabetic and normal hamster hearts. Level of blood glucose, lipoprotein was determined using biocehemical methods. Apoptosis of cardiomyocyte was measured using TUNEL methods. Radioimmunuoassay method was used to determine the level of angiotensin Ⅱ. RT-PCR was used to determine chymase gene expression （ corrected byβ-actin）. Results Comparing with the control group, levels of serum glucose, TG, TC, LDL in DM group were much higher. Concentrations of collagen Ⅰ , Ⅲand angiotensin Ⅱ [ （95.8 ±16.0）μg/kg tissue vs （51.1 ±20. 8）p^g/kg tissue] in myocardial tissue in DM group were much higher than those in control group. RT-PCR result showed： Comparing with the control group, the mRNA expression of chymase in DM group was promoted significantly （0. 810 ±0. 026 vs 0. 490 ± 0. 087）. Conclusion In diabetic hamsters, the gene expression of chymase were much higher than that in the control group, accompanying higher level of Angiotensin Ⅱ , higher levels of expression of collagen Ⅰ and Ⅲ. This result suggests that chymase plays an important role in the diabetic cardiomyopathy by promoting the activity of chymase.

关 键 词：CHYMASE 糖尿病心肌病变 仓鼠 

分 类 号：R587.1[医药卫生—内分泌]