title: Is thickening of the basal lamina in the saphenous vein a hallmark of smoking?
abstract: OBJECTIVE
  To investigate whether smoking causes ultrastructural changes in the intima of the proximal saphenous vein.
  
  
  METHODS
  Proximal saphenous veins from heavy smokers and non-smokers were examined with scanning and transmission electron microscopy to determine changes in surface ultrastructure, in the intercellular junction, and in the thickness of the basal lamina. Immunogold labelling was used to identify specific components of the endothelial basal lamina.
  
  
  METHODS
  Vein specimens were obtained from patients undergoing varicose vein surgery (12 patients) or distal bypass surgery (eight patients).
  
  
  RESULTS
  The only ultrastructural change that discriminated between specimens was thickening of the endothelial basal lamina. All specimens with a thickened basal lamina were from heavy smokers. Immunogold labelling studies showed that the thickened basal lamina contained specific accumulations of fibronectin but not heparan sulphate proteoglycans, type IV collagen, or laminin.
  
  
  CONCLUSIONS
  Two ultrastructural characteristics are associated with smoking: thickening of the endothelial basal lamina and a specific accumulation of fibronectin in the thickened basal lamina. Such abnormalities in the saphenous veins from smokers may contribute to the poorer performance of these veins as bypass conduits.
authors.affiliation: Department of Surgery, Charing Cross and Westminster Medical School, London.
authors.forename: D J
authors.initials: DJ
authors.lastname: Higman
authors.forename: J T
authors.initials: JT
authors.lastname: Powell
authors.forename: R M
authors.initials: RM
authors.lastname: Greenhalgh
authors.forename: A
authors.initials: A
authors.lastname: Coady
authors.forename: J
authors.initials: J
authors.lastname: Moss
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001485:Basement Membrane / Q000737:chemistry / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000737:chemistry; D005260:Female; D005353:Fibronectins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000737:chemistry; D012501:Saphenous Vein / Q000737:chemistry / Q000648:ultrastructure*; D012907:Smoking / Q000473:pathology*
chemical_list: D005353:Fibronectins