豚鼠发育过程前庭上皮细胞增殖和凋亡的关系

The relationship between cell proliferation and apoptosis of vestibular epithelium in the developing guinea pig

目的 研究豚鼠胚胎正常发育过程中前庭上皮细胞增殖和细胞凋亡的变化 ,探讨两者之间的关系及在前庭终器发育中的作用。方法 选用不同发育期正常豚鼠 2 0只 ,取前庭上皮组织切片 ,用免疫组化法检测增殖细胞核抗原 (proliferationcellnuclearantigen ,PCNA) ,以末端脱氧核苷酸转移酶介导的生物dUTP缺口末端标记技术 (TdT mediateddeoxyuridinetriphosphate biotinnickendlabelling,TUNEL)和透射电镜观察细胞凋亡。结果 PCNA阳性细胞为支持细胞 ,毛细胞无阳性反应 ,随年龄增加 ,阳性细胞数逐渐减少。TUNEL阳性反应可发生于毛细胞和支持细胞 ,随年龄增加 ,阳性细胞数逐渐减少 ;出生后壶腹嵴阳性毛细胞位于其顶部。电镜下胚胎期毛细胞和支持细胞均可发生凋亡。结论 发育过程中 ,豚鼠内耳前庭上皮细胞增殖与细胞凋亡数目均逐渐减少 ,凋亡和增殖同时存在 ,自动调节正常细胞数目 。

Objective The cell proliferation and apoptosis of vestibular epithelium in normal developing guinea pig were observed to elucidate the relationship and effect between proliferation and apoptosis in developing vestibular epithelium. Methods Twenty Guinea pigs with different developing ages were used in our studies. Cell proliferation was detected by proliferation cell nuclear antigen (PCNA) immunocytochemistry while apoptosis was detected by TdT mediated deoxyuridine triphosphate biotin nick end labelling (TUNEL) method and transmission electro microscopy. Results PCNA staining had been detected in supporting cells but not in hair cells, and the positive cells were gradually decreased with ageing. The differentiated hair cells and supporting cells underwent apoptosis in vestibular sensory epithelium, and TUNEL positive cells were also markedly decreased with ageing. After birth, TUNEL positive hair cells were located at the top of ampulla. Conclusion During the development of guinea pig, cell proliferation as well as apoptosis events diminish contemporaneously. The balance between proliferation and apoptosis may regulate the normal number of cells, and is related to guarantee the normal structure and function of inner ear.