小鼠肾发育中集合管细胞的超微结构变化及AQP-4的表达

Ultrastructural Changes of Collecting Duct Cells and Expression of AQP-4 during Mouse Kidney Development

目的观察小鼠肾发育过程中集合管细胞的超微结构变化及水通道蛋白4（AQP-4）的表达,探讨AQP-4与小鼠肾集合管细胞发育的关系及作用。方法应用透射电镜、免疫组织化学、免疫印迹技术,并结合体视学方法观察并检测胚龄14,16,18d胎鼠及生后1,3,7,14,21,42 d仔鼠肾发育过程中集合管细胞的超微结构变化及AQP-4的表达。结果小鼠胚龄18 d可见发育早期的主细胞。生后7~21 d,主细胞形态结构发育基本完善。A型闰细胞在胚胎18 d出现,B型闰细胞生后21 d出现。AQP-4于胚龄14 d表达在集合管细胞的基底膜和侧膜,随着胚龄的增加表达逐渐增强,于生后1 d达到高峰。结论集合管细胞在胚胎时期出现,但其形态结构在生后才逐渐完善。AQP-4对胚胎期小鼠肾脏水平衡的调节起了重要的作用,而在生后只起辅助性作用。

Objective To observe ultrastructural changes of collecting duct cells and expressions of AQP-4 during mouse kidney development,in order to investigate their relationships and effects.Methods Transmission electron microscopy,immunohistochemistry,Western blotting,and stereological methods were used to detect morphological changes of collecting duct cells and the expression of AQP-4 in mouse kidney of embryonic day14,16,18 and postnatal day 1,3,7,14 21 and 42.Results The collecting duct principle cells occurred at embryonic day 18.Morphological structures of principle cells were well-developed during postnatal day 7 to 21.A-type intercalated cells occurred at embryonic day 18.B-type intercalated cells occurred at postnatal day 21.AQP-4 was apparently noticed on the based and sliding membrane at embryonic day 14.The expression of AQP-4 increased and reached peak level at postnatal day 1.Conclusion Collecting duct cells emerge during the mouse embryonic development.Their morphological structures are well-developed after birth.AQP-4 is contributed to balance of water in kidney before birth,while is assistant after birth.