Department of Colorectoanal Surgery and Institute of Clinical Medicine, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, China.
Pediatr Nephrol. 2012 Jan;27(1):83-94. doi: 10.1007/s00467-011-1878-x. Epub 2011 Oct 25.
Previously we demonstrated that neonatally induced partial unilateral ureteral obstruction (PUUO) in rats is associated with changes in the abundance of renal acid-base transporters that were paralleled by reduction in renal functions dependent on the severity and duration of obstruction. The aim of the present study was to identify whether changes in renal aquaporin abundance are age-dependent. Semiquantitative immunoblotting and immunohistochemistry were used to examine the changes in abundance of AQP1, AQP2, p-S256AQP2 (AQP2 phosphorylated at consensus site Ser(256)) and AQP3 in the kidneys of rats with neonatally induced PUUO within the first 48 h of life, and then monitored for 7 or 14 weeks. Protein abundance of AQP2 and AQP3 increased in both obstructed and non-obstructed kidneys 7 weeks after induction of neonatal PUUO (PUUO-7W). In contrast, AQP1 and AQP2 protein abundance in the obstructed kidney were reduced after 14 weeks of PUUO (PUUO-14W). Importantly, pS256-AQP2 protein abundance was reduced in obstructed kidneys of both PUUO-7W and PUUO-14W. Immunohistochemistry confirmed the persistent pS256-AQP2 downregulation in both PUUO-7W and PUUO-14W rats. The study shows that the protein abundance of AQP1, AQP2, and AQP3 in the obstructed kidney is increased in PUUO-7W, which may be a compensatory phenomenon and reduced in PUUO-14W rats suggesting a time-/age-dependent dysregulation in response to PUUO. pS256-AQP2 protein abundance is reduced consistent with obstruction-induced direct effects in the apical part of the collecting duct principal cells in response to PUUO.
先前我们已经证明，在新生大鼠中诱导单侧输尿管部分梗阻（PUUO）与肾脏酸碱转运体的丰度变化有关，这些变化与梗阻的严重程度和持续时间有关的肾功能降低相平行。本研究的目的是确定肾脏水通道蛋白丰度的变化是否与年龄有关。半定量免疫印迹和免疫组织化学用于检测在生命的头 48 小时内诱导新生大鼠 PUUO 后，肾脏中 AQP1、AQP2、p-S256AQP2（AQP2 在保守位点 Ser（256）磷酸化）和 AQP3 的丰度变化，然后监测 7 或 14 周。在 PUUO 诱导后 7 周（PUUO-7W），AQP2 和 AQP3 的蛋白丰度在梗阻和非梗阻肾脏中均增加。相比之下，在 PUUO 14 周后（PUUO-14W），梗阻肾脏中的 AQP1 和 AQP2 蛋白丰度降低。重要的是，在 PUUO-7W 和 PUUO-14W 大鼠的梗阻肾脏中，pS256-AQP2 蛋白丰度降低。免疫组织化学证实，在 PUUO-7W 和 PUUO-14W 大鼠中，pS256-AQP2 持续下调。研究表明，在 PUUO-7W 中，梗阻肾脏中 AQP1、AQP2 和 AQP3 的蛋白丰度增加，这可能是一种代偿现象，而在 PUUO-14W 大鼠中减少，表明对 PUUO 的反应存在时间/年龄依赖性失调。pS256-AQP2 蛋白丰度降低与 PUUO 引起的主细胞顶端集合管的直接影响一致。
