title: SPAK-knockout mice manifest Gitelman syndrome and impaired vasoconstriction.
abstract: Polymorphisms in the gene encoding sterile 20/SPS1-related proline/alanine-rich kinase (SPAK) associate with hypertension susceptibility in humans. SPAK interacts with WNK kinases to regulate the Na(+)-K(+)-2Cl(-) and Na(+)-Cl(-) co-transporters [collectively, N(K)CC]. Mutations in WNK1/4 and N(K)CC can cause changes in BP and dyskalemia in humans, but the physiologic role of SPAK in vivo is unknown. We generated and analyzed SPAK-null mice by targeting disruption of exons 9 and 10 of SPAK. Compared with SPAK(+/+) littermates, SPAK(+/-) mice exhibited hypotension without significant electrolyte abnormalities, and SPAK(-/-) mice not only exhibited hypotension but also recapitulated Gitelman syndrome with hypokalemia, hypomagnesemia, and hypocalciuria. In the kidney tissues of SPAK(-/-) mice, the expression of total and phosphorylated (p-)NCC was markedly decreased, but that of p-OSR1, total NKCC2, and p-NKCC2 was significantly increased. We observed a blunted response to thiazide but normal response to furosemide in SPAK(-/-) mice. In aortic tissues, total NKCC1 expression was increased but p-NKCC1 was decreased in SPAK-deficient mice. Both SPAK(+/-) and SPAK(-/-) mice had impaired responses to the selective α(1)-adrenergic agonist phenylephrine and the NKCC1 inhibitor bumetanide, suggesting that impaired aortic contractility may contribute to the hypotension of SPAK-null mice. In summary, SPAK-null mice have defects of NCC in the kidneys and NKCC1 in the blood vessels, leading to hypotension through renal salt wasting and vasodilation. SPAK may be a promising target for antihypertensive therapy.
authors.affiliation: Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Sung-Sen
authors.initials: SS
authors.lastname: Yang
authors.forename: Yi-Fen
authors.initials: YF
authors.lastname: Lo
authors.forename: Chin-Chen
authors.initials: CC
authors.lastname: Wu
authors.forename: Shu-Wha
authors.initials: SW
authors.lastname: Lin
authors.forename: Chien-Ju
authors.initials: CJ
authors.lastname: Yeh
authors.forename: Pauling
authors.initials: P
authors.lastname: Chu
authors.forename: Huey-Kang
authors.initials: HK
authors.lastname: Sytwu
authors.forename: Shinichi
authors.initials: S
authors.lastname: Uchida
authors.forename: Sei
authors.initials: S
authors.lastname: Sasaki
authors.forename: Shih-Hua
authors.initials: SH
authors.lastname: Lin
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology; D004195:Disease Models, Animal; D004232:Diuretics / Q000494:pharmacology; D005260:Female; D005665:Furosemide / Q000494:pharmacology; D053579:Gitelman Syndrome / Q000378:metabolism* / Q000503:physiopathology*; D006852:Hydrochlorothiazide / Q000494:pharmacology; D007022:Hypotension / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D017346:Protein Serine-Threonine Kinases / Q000172:deficiency* / Q000235:genetics; D049992:Sodium Chloride Symporters / Q000378:metabolism; D028021:Sodium-Potassium-Chloride Symporters / Q000378:metabolism; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology*
chemical_list: D004232:Diuretics; D049992:Sodium Chloride Symporters; D028021:Sodium-Potassium-Chloride Symporters; D006852:Hydrochlorothiazide; D005665:Furosemide; C486407:Stk39 protein, mouse; C534421:OXSR1 protein, mouse; D017346:Protein Serine-Threonine Kinases
references.citation: Biochem Biophys Res Commun. 1997 Aug 18;237(2):318-24
references.pmid: 9268708
references.citation: Arch Biochem Biophys. 1998 Jul 15;355(2):233-40
references.pmid: 9675032
references.citation: J Hum Genet. 1999;44(2):116-20
references.pmid: 10083736
references.citation: J Biol Chem. 2003 Dec 26;278(52):52848-56
references.pmid: 14563843
references.citation: Biochem J. 2008 Jan 15;409(2):321-31
references.pmid: 18092945
references.citation: Kidney Int. 2008 Dec;74(11):1403-9
references.pmid: 18800028
references.citation: Am J Physiol. 1995 Dec;269(6 Pt 1):C1496-505
references.pmid: 8572179
references.citation: J Cell Sci. 2008 Mar 1;121(Pt 5):675-84
references.pmid: 18270262
references.citation: Nat Genet. 1996 Jan;12(1):24-30
references.pmid: 8528245
references.citation: Am J Physiol Heart Circ Physiol. 2002 Nov;283(5):H1846-55
references.pmid: 12384462
references.citation: Am J Physiol Heart Circ Physiol. 2007 Oct;293(4):H2039-53
references.pmid: 17693546
references.citation: Biochem Biophys Res Commun. 2010 Mar 19;393(4):844-8
references.pmid: 20175999
references.citation: J Clin Endocrinol Metab. 2005 May;90(5):2500-7
references.pmid: 15687331
references.citation: Endocrinology. 2010 Apr;151(4):1829-36
references.pmid: 20181799
references.citation: Curr Opin Nephrol Hypertens. 2008 Sep;17(5):519-25
references.pmid: 18695394
references.citation: Am J Physiol. 1999 Jun;276(6):C1383-90
references.pmid: 10362601
references.citation: Br J Pharmacol. 2004 Jun;142(3):479-84
references.pmid: 15148259
references.citation: Am J Kidney Dis. 2007 May;49(5):693-700
references.pmid: 17472852
references.citation: Naunyn Schmiedebergs Arch Pharmacol. 2002 Mar;365(3):193-9
references.pmid: 11882915
references.citation: Proc Natl Acad Sci U S A. 2009 Mar 17;106(11):4384-9
references.pmid: 19240212
references.citation: Pflugers Arch. 2004 Oct;449(1):42-55
references.pmid: 15293051
references.citation: Am J Physiol Heart Circ Physiol. 2007 May;292(5):H2100-5
references.pmid: 17259435
references.citation: Oncogene. 2000 Aug 31;19(37):4290-7
references.pmid: 10980603
references.citation: J Cell Sci. 2008 Oct 15;121(Pt 20):3293-304
references.pmid: 18843116
references.citation: J Biol Chem. 2006 Sep 29;281(39):28755-63
references.pmid: 16887815
references.citation: Biochem J. 2005 Oct 1;391(Pt 1):17-24
references.pmid: 16083423
references.citation: Science. 2001 Aug 10;293(5532):1107-12
references.pmid: 11498583
references.citation: Nat Genet. 1996 Jun;13(2):183-8
references.pmid: 8640224
references.citation: Proc Natl Acad Sci U S A. 2009 Jan 6;106(1):226-31
references.pmid: 19114657
references.citation: Kidney Int. 2007 Jan;71(1):74-8
references.pmid: 17082757
references.citation: Am J Physiol Renal Physiol. 2007 Oct;293(4):F1231-7
references.pmid: 17652376
references.citation: J Biol Chem. 2002 Dec 27;277(52):50812-9
references.pmid: 12386165
references.citation: Hypertension. 2003 May;41(5):1131-5
references.pmid: 12668585
references.citation: J Biol Chem. 1997 Jun 27;272(26):16364-73
references.pmid: 9195943
references.citation: Am J Physiol Cell Physiol. 2001 Aug;281(2):C579-84
references.pmid: 11443057
references.citation: Genome Res. 2003 Mar;13(3):476-84
references.pmid: 12618378
references.citation: Ann Saudi Med. 2005 Nov-Dec;25(6):453-8
references.pmid: 16438452
references.citation: Cell Metab. 2007 May;5(5):331-44
references.pmid: 17488636
references.citation: Biochem J. 2006 Jul 1;397(1):223-31
references.pmid: 16669787
references.citation: Am J Physiol Heart Circ Physiol. 2007 May;292(5):H2035-6
references.pmid: 17308011
references.citation: J Biol Chem. 2005 Dec 30;280(52):42685-93
references.pmid: 16263722
references.citation: Hum Mol Genet. 2009 Oct 15;18(20):3978-86
references.pmid: 19633012
references.citation: Scott Med J. 1986 Jan;31(1):43-4
references.pmid: 3961473
references.citation: EMBO Mol Med. 2010 Feb;2(2):63-75
references.pmid: 20091762
references.citation: J Biol Chem. 1998 Oct 30;273(44):29150-5
references.pmid: 9786924