Original Article

Pediatric Nephrology

, Volume 27, Issue 1, pp 83-94

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Age-related changes in expression in renal AQPs in response to congenital, partial, unilateral ureteral obstruction in rats

  • Guixian WangAffiliated withDepartment of Colorectoanal Surgery and Institute of Clinical Medicine, The First Affiliated Hospital, Zhengzhou UniversityThe Water and Salt Research Center, Aarhus University Hospital–SkejbyInstitute of Clinical Medicine, University of Aarhus
  • , Weitang YuanAffiliated withDepartment of Colorectoanal Surgery and Institute of Clinical Medicine, The First Affiliated Hospital, Zhengzhou University
  • , Tae-Hwan KwonAffiliated withThe Water and Salt Research Center, Aarhus University Hospital–SkejbyDepartment of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University
  • , Zhenzhen LiAffiliated withDepartment of Colorectoanal Surgery and Institute of Clinical Medicine, The First Affiliated Hospital, Zhengzhou UniversityThe Water and Salt Research Center, Aarhus University Hospital–SkejbyInstitute of Clinical Medicine, University of Aarhus
  • , Jianguo WenAffiliated withDepartment of Colorectoanal Surgery and Institute of Clinical Medicine, The First Affiliated Hospital, Zhengzhou University
  • , Sukru Oguzkan TopcuAffiliated withThe Water and Salt Research Center, Aarhus University Hospital–SkejbyInstitute of Clinical Medicine, University of Aarhus
  • , Jens Christian DjurhuusAffiliated withInstitute of Clinical Medicine, University of Aarhus
  • , Søren NielsenAffiliated withThe Water and Salt Research Center, Aarhus University Hospital–SkejbyInstitute of Anatomy, University of Aarhus
  • , Jørgen FrøkiærAffiliated withThe Water and Salt Research Center, Aarhus University Hospital–SkejbyInstitute of Clinical Medicine, University of AarhusDepartment of Clinical Physiology, Aarhus University Hospital-Skejby Email author 

Abstract

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 Ser256) 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.

Keywords

Partial ureteral obstruction AQP1 AQP2 pS256-AQP2 AQP3