作　　者： (方登峰）; (张洪伟）; (古君）; (范康钧）; (梁怀民）; (沈嘉渝）; (张尔永）; (胡佳）;

机构地区： 四川大学华西医院麻醉科,成都610041

出　　处： 《四川大学学报（医学版）》 2017年第5期710-715,共6页

摘　　要： 目的观察糖尿病大鼠自体静脉桥的形态学变化以及骨形态发生蛋白-4(bone morphogenic protein-4,BMP4)和增殖细胞抗原Ki-67在其管壁中的表达与分布情况,初步探讨BMP4在高糖环境下静脉桥增殖重构进程中的潜在作用。方法选用8周龄的48只雄性Sprague-Dawley大鼠,随机分配为非糖尿病组(即血糖正常组,n=24)及糖尿病组(n=24),采用高脂高糖饮食联合链脲佐菌素的诱导方法构建糖尿病大鼠模型。两组大鼠均建立单侧颈外静脉-颈总动脉桥接模型,每组分别于术前,术后1周、2周和4周获取大鼠静脉桥(n=6)。应用HE染色切片测算大鼠静脉桥血管壁的形态学参数,免疫组化观察Ki-67及BMP4在管壁中的表达及分布情况,逆转录-聚合酶链式反应(RT-PCR)和免疫印迹法(Western blot)检测BMP4基因和蛋白在静脉桥中的表达量。结果在大鼠静脉桥增殖重构进程中,管壁随时间进展不断增厚,而糖尿病大鼠术后内膜和中膜厚度均高于同期的正常大鼠(P<0.05)。免疫组化提示Ki-67表达于大鼠静脉桥管壁平滑肌细胞的胞核,Ki-67的阳性表达随桥血管增殖重构进程逐渐增高,而术后糖尿病大鼠静脉桥内Ki-67的阳性细胞数高于同期的正常大鼠(P<0.05)。免疫组化提示BMP4表达于大鼠静脉桥管壁平滑肌细胞的胞浆,结合RT-PCR及Western blot检测发现,正常大鼠术后静脉桥中仅有少量BMP4的表达,而糖尿病大鼠静脉桥管壁内BMP4的阳性细胞数以及在基因和蛋白水平的表达量均随时间进展逐渐增高,并高于术后同期的正常大鼠(P<0.05)。结论糖尿病大鼠静脉移植术后桥血管增殖性重构改变与管壁内BMP4的高表达密切相关,而BMP4可能在高糖环境下静脉桥加速失效进程中发挥了重要的促进作用。 Objective This study was designed to assess the vessel wall characteristics and the expression levels of bone morphogenie protein-4 （BMP4） and proliferating cell antigen Ki-67 in vein grafts harvested from diabetic rats, and to investigate the role of BMP4 in progression of vein graft hyperplastic remodeling under hyperglycemic condition. Methods 48 male Sprague-Dawky rats -body mass （194-4-16） g3 aged 8 weeks were randomly divided into diabetes mellitus （DM） group （n= 24） and non-diabetes mellitus （NDM） group （n=24）. The DM rats were induced by streptozotocin in combination with high-sugar and high-fat diet. The unilateral external jugular vein was interposition grafted into the common carotid arteries in the two groups. The vein grafts were harvested at preoperatively and 1, 2 and 4 weeks postoperatively （n=6） in each group. The morphological characteristics of the venous graft wall were evaluated by hcmatoxylin-eosin staining, and the expression levels and the distribution of Ki-67 and BMP4 were assessed by immunohistochemistry analysis, then the expression of BMP4 gene and protein was measured by real-time polymerase chain reaction （RT-PCR） and Western blot assay respectively. Results In the progression of rats vein grafts hyperplastic remodeling, the venous wall thickness of rats thickened with time increasing, and the intimal and medial thickness of the vein grafts harvested from DM rats were significantly higher than those from NDM rats at the same time postoperatively （P〈0.05）. Ki-67 was highly xpressed in smooth muscle cells nucleus located in the rats vein grafts, and its expression level was up-regulatedgradually in the progression of vein graft failure, and the Ki-67 positive cells of vein grafts from DM rats were significantly higher than those from NDM controls at the same period （P〈0.05）. Immunohistochemistry analysis showed that BMP4 was expressed in smooth muscle cells cytoplasmof the rats vein grafts,combined with the results of RT-PCR and Western blot

关 键 词： 骨形态发生蛋白 高糖环境 冠状动脉旁路移植术 静脉桥