动物造模,急性心肌梗死 z-bio 2022-10-18 334

　　Objective To investigate the effect and mechanism of cord blood mononuclear cells (HCMNCs) on angiogenesis in rats with acute myocardial infarction (AMI).

　　Methods HCMNCs were isolated and labeled with BrdU. Twenty five rats were selected to establish acute myocardial infarction model by coronary artery ligation. Twenty rats were randomly divided into myocardial infarction group, HCMNCs group, 10 rats in each group, and 10 rats in the sham operation group. After successful modeling, HCMNCs were injected around myocardial infarction in HCMNCs group, and L-DMEM culture medium was injected at the same site in sham operation group and model group. Four weeks after transplantation, echocardiography was used to detect cardiac function, HE staining was used to observe myocardial pathological changes, BrdU staining was used to detect the survival of transplanted cells, immunohistochemistry staining was used to detect the expression of microvessel density (MVD), CD31, vascular endothelial growth factor (VEGF) proteins at the edge of myocardial infarction, and Western blot was used to detect the levels of CD31 and VEGF proteins in myocardial tissue.

　　Results Compared with sham operation group, the levels of left ventricular end systolic diameter (LVEDs) and left ventricular end diastolic diameter (LVEDd) in myocardial infarction group and HCMNCs group increased, while the levels of left ventricular ejection fraction (LVEF) and left ventricular short axis shortening rate (FS) decreased (P<0.05); Compared with myocardial infarction group, the levels of LVEDs and LVEDd in HCMNCs group decreased, while the levels of LVEF and FS increased (P<0.05). HE staining showed that the structure of myocardial cells in sham operation group was normal, but the arrangement of myocardial cells in myocardial infarction group was disordered, with a large number of inflammatory cells infiltrating; The structure of myocardial cells in HCMNCs group was basically normal. BrdU staining showed that no BrdU labeled positive cells were detected in the sham operation group and myocardial infarction group, and scattered BrdU positive cells were found in the infarct area of HCMNCs group, which participated in the composition of the vascular wall. Compared with sham operation group, CD31, VEGF protein light density, relative protein expression and MVD decreased in myocardial infarction group and HCMNCs group (P<0.05); Compared with myocardial infarction group, CD31, VEGF protein light density, relative protein expression and MVD in HCMNCs group increased (P<0.05).

　　Conclusion HCMNCs can promote the establishment of collateral circulation, induce angiogenesis, and improve ischemic cardiac function in AMI rats.