摘要
目的:观察急性心肌梗死大鼠行骨髓间质干细胞移植后受损心肌组织的病理形态学变化。方法:实验于2004-01/2005-06在上海胸科医院完成。选取健康成年雌性SD大鼠40只,随机数字表法分为骨髓间质干细胞注射组、模型对照组,20只/组。①两组大鼠均建立心肌梗死模型。造模0.5h后,骨髓间质干细胞注射组于结扎点下方缺血区域组织注射Dill标记的骨髓间质干细胞3×106个,模型对照组心肌缺血区域注射100μL生理盐水。②造模后4～6周处死两组大鼠,取出心脏,剪除双侧心房及右心室,沿左心室长轴由心尖到底部做3mm厚切片,镜下观察心肌梗死区域病理组织学表现。③选择心肌梗死表现明显的蜡块切片,行酸性复红染色,用LeicaQWin多媒体彩色病理图文分析软件进行图像分析,自动测量出切片中心肌梗死组织占总面积的百分比。免疫组化检测梗死心肌血管内皮生长因子和FactorⅧ蛋白因子的表达情况。结果:40只大鼠均进入结果分析。①梗死心肌的病理形态学观察:光镜下两组均可见大小不等的心肌梗死灶,梗死心肌区域细胞肿胀坏死,严重缺血坏死区出现心肌溶解。但骨髓间质干细胞注射组上述改变明显弱于模型对照组,其心肌梗死中层可见条索状的梗死灶及纤维瘢痕灶,并且有残存的心肌呈岛状散在分布,纤维瘢痕区域心肌细胞、微血管和毛细血管数量均明显增加,侧支循环丰富。另外,骨髓间质干细胞移植组于造模初期4只大鼠心内膜面有灶性软骨生成,向心室腔突起。②梗死心肌面积百分率的检测:骨髓间质干细胞注射组梗死心肌面积百分率明显低于模型对照组[(3.69±0.48)%,(19.20±1.77)%,t=7.621～10.820,P=0.001]。③梗死心肌血管内皮生长因子和FactorⅧ免疫组化检测:骨髓间质干细胞注射组血管内皮生长因子、FactorⅧ呈阳性表达,模型对照组未检测到血管内皮生长因子和FactorⅧ。结论:骨髓间质干细胞在大鼠心脏内可以转化为血管内皮细胞或分泌血管内皮生长因子,是治疗缺血性心血管疾病理想的细胞来源。心内膜面有灶性软骨生成可能是由于注射细胞时进针太深,警示注意骨髓间质干细胞移植的副反应。
AIM： To study the pathomorphoiogical variance of injured myocardial tissues with acute myocardial infarction after transplantation of mesenchymal stem cells （MSCs） in rats. METHODS： This experiment had been finished in Shanghai Chest Hospital during January 2004 to June 2005. Forty healthy female SD rats were allocated into experimental group and control group, with 20 rats in each. （1）A rat model of acute myocardial infarction was built in two groups. Half an hour later, the experimental group were injected with Dill-labeled 3×10^6 MSCs in the ischemic tissues under the deligation; while the control group received the saline of 100 μL. （2）Rat were executed 4-6 weeks later for the removal of cardiac atrium and right ventricle. A cardiac section of 3-mm thick was dissected along the long axis of left ventricle, arranging from cardiac apex to bottom. Then pathohistological appearance of myocardial infarction area was observed by microscope. （3）The paraffin section that obviously suffered myocardial infarction were stained by acid fuchsin, and Leica Q Win multimedia software was used for the image analysis. The percentage of myocardial infarction area of total area was measured, the expression of monocional antibody vascular endothelial growth factor （VEGF） and Factor Ⅷ in myocardial infarction area was examined by immunohistochemical method. RESULTS： Totally 40 rats were involved in the result analysis.（1）Pathomorphology observation of infracted myocardium： The result of microscope demonstrated that myocardial infarction of uneven size appeared in both groups accompanying cellular swelling and necrosis, additionally cardiac myolysis was found in the severely ischemic area. All above variances were more notable in control group than in experimental group, which showed trabs lesions for infarction and fiber scars while resident myocardium scattered. In the experimental group, there were increased trend of myocardial cells and capillary quantity obviously, and abundant collateral circulation. Moreover, local cartilage appeared in the endocardial surface of 4 rats and emerged toward ventricular chamber.（2）The percentage of myocardial infarction area was obviously less in experimental group than in control group [（3.69±0.48）%, （19.20±1.77）%, t =7.621-10.820, P =0.001].（3）VEGF and Factor Ⅷ were positively expressed in the experimental group, whereas no expression was assayed in the control group. CONCLUSION： MSCs can be transformed into vascular endothelial cells or secrete VEGF in rat hearts, thus is the ideal cell source of therapy in ischemic cardiovascular disease. Local cartilage may appear due to too deep needling during injection, suggesting that operation should be standard executed in MSC transplantation to prevent from side effect.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2007年第3期486-489,I0004,共5页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
上海市科委研究项目资助(034119856)~~
