发育期小鼠肾小体细胞增殖与凋亡的研究

STUDY ON PROLIFERATION AND APOPTOSIS IN DEVELOPING RENAL CORPUSCLES OF MOUSE

目的研究小鼠肾小体发育过程中细胞增殖与凋亡的变化规律。方法采用PCNA免疫组织化学方法、末端脱氧核苷酸转移酶介导的缺口末端标记法(TUNEL染色法)和光、电镜技术,对发育不同阶段肾小体的细胞增殖和凋亡进行观察。结果PCNA免疫组织化学染色显示:在Ⅰ和Ⅱ期肾小体内几乎所有细胞PCNA呈强阳性反应,Ⅲ、Ⅳ期肾小体PCNA阳性细胞数逐渐减少,Ⅴ期肾小体PCNA阳性细胞少见。TUNEL阳性细胞多出现在出生前,主要在Ⅲ、Ⅳ期肾小体表达。电镜观察:早期肾小体所有细胞核分裂象机率均高,Ⅲ期肾小体中的内皮细胞、足细胞核分裂象机率高,Ⅳ期肾小体中只见到内皮细胞核分裂象,Ⅴ期细胞核分裂象少见。电镜下所见的细胞凋亡多在Ⅲ、Ⅳ期肾小体,其中以内皮细胞、肾小囊壁层细胞凋亡居多。结论细胞增殖与凋亡行为在小鼠肾小体发育的整个过程中普遍存在,协同参与了调控肾小体正常发育过程。

Objective To study cell proliferation and apoptosis of renal corpuscle in normal developing mouse. Methods PCNA immunohistochemisty method, terminal deoxynucleotidyl transferase mediated dUTP-biotin nick endlabeling（TUNEL staining method）and light, electron microscopy were used to observe proliferation and apoptosis within corpuscle at different stages of development. Results Nearly all cells in Ⅰ and Ⅱ stages had nuclear PCNA immunolabeling. The number of PCNA immunolabeling cells during Ⅲ and Ⅳ stages was gradually decreased, and to less in Ⅴ stage. TUNEL positive cells could be easily observed before birth and identified in Ⅲ and Ⅳ stages. Electron microscope revealed that the mitotic activity was observed in all cells of Ⅰ and Ⅱ stages renal corpuscles. The mitotic phases of endothelial cells and podocytes could be seen in Ⅲ stage, but only endothelial mitotic activities in Ⅳ stage of renal corpuscle. Apoptotic activities of endothelial cell and Bowman＇ s parietal cell were noted, predominantly in m and Ⅳ stages. Conclusion Proliferation and apoptosis exist universally in the course of developing renal corpuscle, and supervise and control the regular development of renal corpuscle cooperatively.