摘要
目的探讨在异丙肾上腺素诱导的心肌缺血坏死大鼠模型中,干细胞标记物阳性细胞参与坏死区自发性再生。方法按4mg/kg剂量连续皮下注射异丙肾上腺素7d,制备大鼠缺血坏死动物模型。通过形态学、免疫荧光和Ed U示踪等技术,研究心肌缺血坏死区形态变化、干细胞和心肌细胞标记物表达和增殖细胞的特征。结果组织病理学观察显示缺血坏死区限制在近心内膜的心肌组织,早期坏死区存在呈强嗜酸性圆/椭圆或细棒形细胞,超微结构显示细棒形细胞具幼稚心肌细胞特征;免疫荧光技术显示坏死区呈c-kit+/gata+细胞、CD34+/gata+细胞、CD34+/factorⅧ+细胞;Ed U标记显示新增殖的细胞呈c Tn I阳性。结论 C-kit、nanog和CD34阳性干细胞参与坏死区的修复,坏死区产生了幼稚的心肌细胞,CD34+干细胞参与坏死区微血管形成。
Objective The notion of the adult heart as a terminally differentiated organ without the potential for self-renewal has been undermined by the identification of a subpopulation of proliferating cardiomyoeytes in both the healthy and pathological states. Our purpose is to determine whether the expression of stem cell markers was associated with the spontaneous regeneration of cardiomyocytes in rats following isoproterenol hydrochloride （ ISO）-induced cardiac necrosis. Methods Rats （n = 40） were injected subcutaneously with 4 mg/（ kg. d） ISO for 7 days. The morphological structures were observed, the expression of stem cell and caridomyocyte markers were detected, and the characteristics of proliferation cell were surveyed in the necrotic area utilizing morphology, immunofluorescene and EdU labeling technology. Results The histopathological examination showed that the ischemic necrosis was limited to the area of the myocardium near the endocardium. A small number of round or ellipsoid and rod-shaped ceils with strongly stained acidophilic cytoplasm were dispersed throughout the necrotic LV tissue. The uhrastrueture analyses showed that the rod-shaped cells had the features similar to those of naive cardiomyocytes. The immunofluorescent staining showed that c-kit ^＋/gata ^＋ cells, nanog ＋ ceils, CD34^＋/gata ^＋ cells and CD34^＋/factor Ⅷ^＋ cells were present in the necrotic tissue. The EdU labeling showed that the cTnI ＋ cells in the necrotic area were actively proliferating cardiomyocytes. Conclusion Cardiac stem cells expressing c- kit, nanog, or CD34 participate in the spontaneous regeneration of necrotic area caused by ISO. The naive cardiomyocytes are formed in necrotic area. The CD34^ ＋ stem cells participate in the repair of the micro-vessel in the necrotic area of the myocardium.
出处
《解剖学报》
CAS
CSCD
北大核心
2015年第6期824-831,共8页
Acta Anatomica Sinica
基金
Scientific Research Fund of Xinxiang Medical University(2013ZD121)
