title: The timeline of lamellar basement membrane changes during equine laminitis development.
abstract: BACKGROUND
  The timing of lamellar basement membrane (BM) changes occurring during laminitis development is incompletely understood.
  
  
  OBJECTIVE
  To determine the temporal progression of lamellar BM changes and whether laminin-332 (Ln-332) γ2 cleavage products are generated during laminitis development.
  
  
  METHODS
  Eight clinically normal Standardbred horses were allocated into treatment (n = 5) or sham (n = 3) groups. The treatment group received, via nasogastric intubation, an oligofructose (OF) bolus (10 g/kg bwt) while the sham group was given water. Laminitis induction proceeded for 48 h followed by euthanasia. Lamellar biopsies were obtained prior to dosing and at intervals during the treatment period for analysis (at 12, 18, 24, 30 and 36 h and at 48 h following euthanasia).
  
  
  RESULTS
  Changes in lamellar collagen type IV and Ln-332 were first observed at 12 h post dosing. A unique pattern of reactivity for the Ln-332 γ2 antibody D4B5 occurred, in which reactivity was observed only in lamellar tissue affected by laminitis. No bioactive Ln-332 γ2 proteolytic fragments were detected in lamellar samples.
  
  
  CONCLUSIONS
  Basement membrane changes occurred early during the laminitis process. Direct Ln-332 γ2 cleavage to release biologically active products did not appear to occur. Thus loss of stability or protein interaction of the BM is probably responsible for the γ2 specific reactivity observed.
  
  
  CONCLUSIONS
  Basement membrane changes may a first step in lamellar failure occurring prior to detection with conventional methods. Thus, more sensitive detection methods of BM changes are required to study laminitis development.
authors.affiliation: The Australian Equine Laminitis Research Unit, School of Veterinary Science, The University of Queensland, St Lucia, Australia.
authors.forename: M B
authors.initials: MB
authors.lastname: Visser
authors.forename: C C
authors.initials: CC
authors.lastname: Pollitt
mesh_terms: D000818:Animals; D001485:Basement Membrane / Q000473:pathology*; D001706:Biopsy / Q000662:veterinary; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D024141:Collagen Type IV / Q000378:metabolism*; D024143:Collagen Type VII / Q000378:metabolism*; D005534:Foot Diseases / Q000473:pathology / Q000662:veterinary*; D006734:Horse Diseases / Q000473:pathology*; D006736:Horses; D015151:Immunoblotting / Q000662:veterinary; D007150:Immunohistochemistry / Q000662:veterinary; D008856:Microscopy, Fluorescence / Q000662:veterinary; D000097794:Kalinin
chemical_list: D015815:Cell Adhesion Molecules; D024141:Collagen Type IV; D024143:Collagen Type VII; D000097794:Kalinin