title: Effects of hyperosmolality on expression of urea transporter A2 and aquaporin 2 in mouse medullary collecting duct cells.
abstract: In this study, the effects of hyperosmolality on the expression of urea transporter A2 (UTA2) and aquaporin 2 (AQP2) were investigated in transfected immortalized mouse medullary collecting duct (mIMCD3) cell line. AQP2-GFP-pCMV6 and UTA2-GFP-pCMV6 plasmids were stably transfected into mIMCD3 cells respectively. Transfected mIMCD3 and control cells were cultured in different hypertonic media, which were made by NaCl alone, urea alone, or an equiosmolar mixture of NaCl and urea. The mRNA and protein expression of AQP2 was elevated by the stimulation of NaCl alone, urea alone and NaCl plus urea in AQP2-mIMCD3 cells; whereas NaCl alone and NaCl plus urea rather than urea alone increased the mRNA and protein expression of UTA2 in UTA2-mIMCD3 cells, and all the expression presented an osmolality-dependent manner. Moreover, the mRNA and protein expression of UTA2 rather than AQP2 was found to be synergistically up-regulated by a combination of NaCl and urea in mIMCD3 cells. It is concluded that NaCl and urea synergistically induce the expression of UTA2 rather than AQP2 in mIMCD3 cells, and hyperosmolality probably mediates the expression of AQP2 and UTA2 through different mechanisms.
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Wenmin
authors.initials: W
authors.lastname: Jin
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Yao
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Taoxia
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Ji
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Yongxia
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China. drylj@hotmail.com.
authors.forename: Lijun
authors.initials: L
authors.lastname: Yao
mesh_terms: D000818:Animals; D051399:Aquaporin 2 / Q000378:metabolism*; D002460:Cell Line; D007685:Kidney Tubules, Collecting / Q000166:cytology* / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D051379:Mice; D009994:Osmolar Concentration; D064587:Osmoregulation / Q000502:physiology*; D021381:Protein Transport / Q000502:physiology; D012965:Sodium Chloride / Q000378:metabolism*; D014508:Urea / Q000378:metabolism*; D000096982:Urea Transporters
chemical_list: D051399:Aquaporin 2; D026901:Membrane Transport Proteins; D012965:Sodium Chloride; D014508:Urea; D000096982:Urea Transporters; C496024:Aqp2 protein, mouse