title: Morphology and hemodynamics during vascular regeneration in critically ischemic murine skin studied by intravital microscopy techniques.
abstract: BACKGROUND
  With the understanding of angiogenesis and arteriogenesis, new theories about the orchestration of these processes have emerged. The aim of this study was to develop an in vivo model that enables visualization of vascular regenerating mechanisms by intravital microscopy techniques in collateral arteriolar flap vascularity.
  
  
  METHODS
  A dorsal skin flap (15 × 30 mm) was created in mice and fixed into a skinfold chamber to allow for assessment of morphology and microhemodynamics by intravital fluorescence microscopy (IVFM). Laser scanning confocal microscopy (LSCM) was utilized for three-dimensional reconstruction of the microvascular architecture.
  
  
  RESULTS
  Flap tpO(2) was 5.3 ± 0.9 versus 30.5 ± 1.2 mm Hg in controls (p < 0.01). The collateral arterioles in the flap tissue were dilated (29.4 ± 5.3 μm; p < 0.01 vs. controls) and lengthened in a tortuous manner (tortuosity index 1.00 on day 1 vs. 1.35± 0.05 on day 12; p < 0.01). Functional capillary density was increased from 121.00 ± 25 to 170 ± 30 cm/cm(2) (day 12; p < 0.01) as a result of angiogenesis. Morphological evidence of angiogenesis on capillary level and vascular remodeling on arteriolar level could be demonstrated by IVFM and LSCM.
  
  
  CONCLUSIONS
  Present intravital microscopy techniques offer unique opportunities to study structural changes and hemodynamic effects of vascular regeneration in this extended axial pattern flap model.
authors: Department of Clinical Researc, University of Bern, Bern, Switzerland.
authors: R
authors: R
authors: Schweizer
authors: K
authors: K
authors: Merz
authors: S
authors: S
authors: Schlosser
authors: T
authors: T
authors: Spanholtz
authors: C
authors: C
authors: Contaldo
authors: J V
authors: JV
authors: Stein
authors: V
authors: V
authors: Enzmann
authors: P
authors: P
authors: Giovanoli
authors: D
authors: D
authors: Erni
authors: J A
authors: JA
authors: Plock
mesh_terms: D000818:Animals; D005260:Female; D006439:Hemodynamics; D007511:Ischemia / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D018919:Neovascularization, Physiologic; D012038:Regeneration; D012867:Skin / Q000098:blood supply* / Q000473:pathology