小鼠后肾集合管水通道蛋白表达及其上皮细胞超微结构研究

Ultrastructural changes of collecting duct cells and expression of AQP-4 during the development of mouse kidney

目的观察小鼠后肾集合管水通道蛋白(AQP)-4的表达及其上皮细胞超微结构变化。方法应用透射电镜、免疫组织化学及图像分析技术观察并检测小鼠后肾不同发育阶段集合管的超微结构及AQP-4表达。结果小鼠胚龄18 d见发育早期集合管主细胞,生后7 d～21 d,其形态结构发育基本完善。A型闰细胞于胚胎18 d出现,B型闰细胞生后21天出现。AQP-4于胚龄14 d始见表达,分布于集合管管壁上皮细胞侧基底细胞膜,随胚龄增加表达逐渐增强,生后1 d达高峰。结论集合管管壁上皮细胞于胚胎时出现,但其形态结构在生后才逐渐完善。AQP-4对小鼠胚胎时期肾水平衡调节可能起重要的作用。

Objective To observe the ultrastructural changes of collecting duct cells and expressions of AQP-4 during the development of mouse kidney. Methods Transmission electron microscopy and immu- nohistochemistry were used to detect the morphological changes of collecting duct cells and the expression of AQP-4 in mouse kidney on embryonic days 14, 16, 18 and postnatal days 1,3,7,14 21 and 40. Results The collecting duct principle cells occurred at embryonic day 18. Morphological structures of principle cells were well - developed during postnatal days 7 to 21. A-type intercalated cells occurred at a peak level at postnatal day 1. Conclusions The study suggested that collecting duct cells emerge dur- ing the mouse embryonic development. Their morphological structures may be well-developed after birth. AQP-4 may play an important role in the water balance regulation in the kidney before birth.