title: Proteomic analysis of formalin-fixed paraffin-embedded glomeruli suggests depletion of glomerular filtration barrier proteins in two-kidney, one-clip hypertensive rats.
abstract: BACKGROUND
  It is well known that hypertension may cause glomerular damage, but the molecular mechanisms involved are still incompletely understood.
  
  
  METHODS
  In the present study, we used formalin-fixed paraffin-embedded (FFPE) tissue to investigate changes in the glomerular proteome in the non-clipped kidney of two-kidney one-clip (2K1C) hypertensive rats, with special emphasis on the glomerular filtration barrier. 2K1C hypertension was induced in 6-week-old Wistar Hannover rats (n = 6) that were sacrificed 23 weeks later and compared with age-matched sham-operated controls (n = 6). Tissue was stored in FFPE tissue blocks and later prepared on tissue slides for laser microdissection. Glomeruli without severe morphological damage were isolated, and the proteomes were analysed using liquid chromatography-tandem mass spectrometry.
  
  
  RESULTS
  2K1C glomeruli showed reduced abundance of proteins important for slit diaphragm complex, such as nephrin, podocin and neph1. The podocyte foot process had a pattern of reduced abundance of transmembrane proteins but unchanged abundances of the podocyte cytoskeletal proteins synaptopodin and α-actinin-4. Lower abundance of important glomerular basement membrane proteins was seen. Possible glomerular markers of damage with increased abundance in 2K1C were transgelin, desmin and acyl-coenzyme A thioesterase 1.
  
  
  CONCLUSIONS
  Microdissection and tandem mass spectrometry could be used to investigate the proteome of isolated glomeruli from FFPE tissue. Glomerular filtration barrier proteins had reduced abundance in the non-clipped kidney of 2K1C hypertensive rats.
authors.affiliation: Department of Clinical Medicine, University of Bergen, Bergen, Norway.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Finne
authors.affiliation: Department of Clinical Medicine, University of Bergen, Bergen, Norway.
authors.forename: Heidrun
authors.initials: H
authors.lastname: Vethe
authors.affiliation: Department of Clinical Medicine, University of Bergen, Bergen, Norway Department of Biomedicine, University of Bergen, Bergen, Norway.
authors.forename: Trude
authors.initials: T
authors.lastname: Skogstrand
authors.affiliation: Department of Clinical Medicine, University of Bergen, Bergen, Norway Department of Pathology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Sabine
authors.initials: S
authors.lastname: Leh
authors.affiliation: Department of Clinical Medicine, University of Bergen, Bergen, Norway Department of Biomedicine, University of Bergen, Bergen, Norway.
authors.forename: Tone D
authors.initials: TD
authors.lastname: Dahl
authors.affiliation: Department of Biomedicine, University of Bergen, Bergen, Norway.
authors.forename: Olav
authors.initials: O
authors.lastname: Tenstad
authors.affiliation: Department of Biomedicine, University of Bergen, Bergen, Norway The Norwegian Multiple Sclerosis National Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Frode S
authors.initials: FS
authors.lastname: Berven
authors.affiliation: Department of Biomedicine, University of Bergen, Bergen, Norway Centre for Cancer Biomarkers (CCBIO), University of Bergen, Bergen, Norway.
authors.forename: Rolf K
authors.initials: RK
authors.lastname: Reed
authors.affiliation: Department of Clinical Medicine, University of Bergen, Bergen, Norway Department of Medicine, Haukeland University Hospital, Bergen, Norway Department of Medicine, Haugesund Hospital, Haugesund, Norway.
authors.forename: Bjørn Egil
authors.initials: BE
authors.lastname: Vikse
mesh_terms: D000818:Animals; D001794:Blood Pressure; D002853:Chromatography, Liquid; D004195:Disease Models, Animal; D005557:Formaldehyde; D060730:Glomerular Filtration Barrier / Q000503:physiopathology*; D006973:Hypertension / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D007674:Kidney Diseases / Q000378:metabolism* / Q000473:pathology; D007678:Kidney Glomerulus / Q000378:metabolism* / Q000473:pathology; D008297:Male; D010232:Paraffin; D011506:Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D051381:Rats; D017208:Rats, Wistar; D053719:Tandem Mass Spectrometry
chemical_list: D011506:Proteins; D020543:Proteome; D005557:Formaldehyde; D010232:Paraffin
keywords: 2K1C; FFPE; glomerulus; hypertension; proteomics