Yamamoto T, Sasaki S, Fushimi K, Ishibashi K, Yaoita E, Kawasaki K, Fujinaka H, Marumo F, Kihara I
Department of Pathology, Institute of Nephrology, Niigata University School of Medicine, Japan.
Am J Physiol. 1997 Feb;272(2 Pt 2):F198-204. doi: 10.1152/ajprenal.1997.272.2.F198.
The mRNA expression and localization of the aquaporin (AQP) family in rat kidney were examined by ribonuclease protection assay and immunohistochemistry. AQP1, AQP2, AQP3, and AQP4 mRNA were hardly detectable in 16-day gestation fetuses. AQP1 mRNA was explosively expressed at 1 wk, keeping the level throughout life. AQP2 mRNA expression was apparently noticed in 18-day fetuses and was enhanced gradually with age to reach a plateau at 4 wk. AQP3 and AQP4 mRNA expression was significantly found at birth but was not changed remarkably thereafter. AQP2 protein appeared first at the apical side of collecting duct cells in 18-day fetuses. The staining intensity at the site increased with age, and basolateral staining was added in adult rats. AQP3 was distinctly demonstrated at the basolateral side of collecting duct cells after birth, and the staining intensity was almost stable throughout life. The progressive induction of AQP2 expression in the first 4 wk after birth is presumed to contribute to the maturation of urinary concentrating capacity during the kidney development.
采用核糖核酸酶保护分析法和免疫组织化学方法检测了水通道蛋白（AQP）家族在大鼠肾脏中的mRNA表达及定位。在妊娠16天的胎儿中几乎检测不到AQP1、AQP2、AQP3和AQP4的mRNA。AQP1的mRNA在出生后1周时呈爆发性表达，并在整个生命过程中保持该水平。AQP2的mRNA在妊娠18天的胎儿中明显可见，并随年龄逐渐增加，在4周时达到平台期。AQP3和AQP4的mRNA在出生时显著表达，但此后无明显变化。AQP2蛋白最早出现在妊娠18天胎儿集合管细胞的顶端。该部位的染色强度随年龄增加，成年大鼠中还出现了基底外侧染色。AQP3在出生后在集合管细胞的基底外侧明显可见，且染色强度在整个生命过程中几乎稳定。出生后前4周AQP2表达的逐渐诱导被认为有助于肾脏发育过程中尿液浓缩能力的成熟。
