RESUMO
Objective To observe the sites and relations of AQP-2 and AQP-4 in kidney during development and maturation, and discuss the roles of them. Methods Immunohistochemistry combined with stereological methods were used to observe and measure the expression of AQP-2 and AQP-4. Results AQP-2 was apparently noticed at the apical side and cytoplasm of principle cells in the collecting ducts. The expression of AQP-2 at the apical side increased from 17-fetuses to 1-day neonatal by stereology, but it hardly changed after 1-day neonatal. The expression of AQP-4 was faint at 14-day embryo and enhanced with age to reach a plateau at birth, and was not changed remarkably thereafter. The expression of AQP-4 was less than AQP-2 in every stage of kidney development. It was localized at the basolateral membrane of ureteric buds or collecting ducts.Conclusion We presume that AQPs are very important for balance of water during development and maturation in mice kidney, while AQP-4 is before birth, AQP-2 is after birth.