title: Splice variants of neuronal nitric oxide synthase are present in the rat kidney.
abstract: BACKGROUND
  Decreased renal cortical neuronal NO synthase (nNOS) abundance/activity correlates with progression of chronic kidney disease (CKD) in a number of animal models.
  
  
  METHODS
  Western blotting with both N-terminal and C-terminal antibodies, immunoprecipitation, proteomics, RT-PCR and in situ hybridization were used to identify nNOS splice variants in the rat kidney.
  
  
  RESULTS
  We have identified two nNOS proteins and transcripts in the rat kidney; nNOSalpha (approximately 160 kDa) and nNOSbeta (approximately 140 kDa), a catalytically active exon-2 deletion variant, lacking both the PDZ and protein inhibitor of nNOS (PIN) domains. We also report that nNOSbeta protein abundance is increased in the kidney at 11 weeks following 5/6th nephrectomy (5/6NX)-induced CKD while nNOSalpha protein abundance is diminished. The transcript data parallel the protein data in 5/6NX. By in situ hybridization, there is abundant nNOSalpha mRNA widely distributed throughout the normal kidney cortex, with very sparse nNOSbeta mRNA confined to a few proximal tubules. In a second injury model (6 weeks after 5/6 renal mass reduction by combined right kidney ablation and infarction of approximately 2/3 of the left kidney; 5/6 A/I), nNOSalpha mRNA almost disappears from the kidney cortex while nNOSbeta mRNA abundance increases in tubules and tubulo-interstitium.
  
  
  CONCLUSIONS
  The renal cortical nNOSbeta protein is present in low abundance in the normal kidney and increases with injury, in an inverse pattern of change with the nNOSalpha.
authors.affiliation: Department of Physiology and Functional Genomics, University of Florida, POB 100274, Gainesville, FL 36210, USA.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Smith
authors.forename: Michael
authors.initials: M
authors.lastname: Merchant
authors.forename: Andrea
authors.initials: A
authors.lastname: Fekete
authors.forename: Ha-Long
authors.initials: HL
authors.lastname: Nyugen
authors.forename: Paul
authors.initials: P
authors.lastname: Oh
authors.forename: You-Lin
authors.initials: YL
authors.lastname: Tain
authors.forename: Jon B
authors.initials: JB
authors.lastname: Klein
authors.forename: Chris
authors.initials: C
authors.lastname: Baylis
mesh_terms: D000818:Animals; D002908:Chronic Disease; D004195:Disease Models, Animal; D005260:Female; D014644:Genetic Variation / Q000235:genetics; D007527:Isoenzymes / Q000378:metabolism; D007672:Kidney Cortex / Q000201:enzymology*; D007674:Kidney Diseases / Q000201:enzymology*; D008297:Male; D009392:Nephrectomy; D052248:Nitric Oxide Synthase Type I / Q000235:genetics / Q000378:metabolism*; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats
chemical_list: D007527:Isoenzymes; D020033:Protein Isoforms; D012333:RNA, Messenger; D052248:Nitric Oxide Synthase Type I