观察小鼠出生后肾脏髓质发育过程中增殖细胞核抗原(proliferatingcellnuclearantigen,PCNA)的表达及细胞凋亡的特征,探讨出生后小鼠肾脏髓质发育过程中细胞增殖与凋亡的规律及其关系。应用免疫组织化学技术和原位末端标记法(TUNEL法)分别检测小鼠出生后1、3、7、14、21、28和70天肾脏髓质中的增殖细胞及凋亡细胞。结果显示,(1)小鼠出生后肾脏髓质发育中PCNA阳性细胞的表达具有一定的规律,早期PCNA阳性表达丰富,随着肾脏发育逐渐成熟而表达减弱;(2)在细胞增殖的同时也存在着细胞凋亡现象,细胞凋亡指数于生后第7天达到高峰,以后表达逐渐减弱。细胞增殖与凋亡在小鼠生后肾脏髓质发育的整个过程中普遍存在,早期细胞增殖旺盛,增殖高峰之后出现凋亡高峰,晚期两者活动均减弱。 To observe the expression of proliferating cell nuclear antigen (PCNA) and the characteristics of cell apoptosis during the development of renal medulla development in mice, and to explore the regularity of cell proliferation and apoptosis during the development of mouse renal medulla. Immunohistochemical technique and TUNEL method were used to detect proliferative and apoptotic cells in renal medulla at 1, 3, 7, 14, 21, 28 and 70 days after birth. The results showed that: (1) The expression of PCNA positive cells in the development of kidney medulla after birth in mice has certain regularity, the expression of PCNA in early stage is rich, and the expression of PCNA is weakening as the kidneys mature; (2) Apoptosis was observed. The apoptotic index peaked on the 7th day after birth, and then gradually decreased. Cell proliferation and apoptosis were prevalent in the whole process of kidney medulla development in postnatal mice. The proliferation of early cells was vigorous, and the peak of apoptosis appeared after the peak of proliferation.