title: Microvascular effects of subatmospheric pressure in striated muscle.
abstract: OBJECTIVE
  Topical application of subatmospheric pressure (TASAP) promotes faster wound healing, but tissue effects are not entirely understood. This study investigated microvascular effects of TASAP in striated muscle with the hypothesis being that TASAP elicits arteriolar vasodilation and decreases interstitial accumulation of protein.
  
  
  METHODS
  Rat cremasteric microcirculation was directly examined in two experiments utilizing a novel technique. First, TASAP was applied to the cremaster in three experimental groups and a non-TASAP control group. Arteriolar diameters were directly measured before and after TASAP. In experiment two, intravascular fluorescein isothiocyanate (FITC)-labeled albumin and topical leukotriene B4 (LTB4) were delivered to the cremaster. Microvascular permeability was assessed by measuring the accumulation/disappearance of FITC-albumin in the interstitial tissue.
  
  
  RESULTS
  TASAP produced significant arteriolar vasodilation compared with control values. The mean maximum percent increase in diameter with TASAP was 8.70% at -2 kPa (p < 0.05), 7.16% at -4 kPa (p < 0.05), and 10.43% at -6 kPa (p < 0.01). TASAP decreased interstitial FITC-albumin by 26.3% (p < 0.008) following LTB4; the control group showed a steady increase in interstitial FITC-albumin.
  
  
  CONCLUSIONS
  These results support the hypothesis that TASAP elicits significant arteriolar vasodilation with a subsequent increase in blood flow as well as a decrease in interstitial protein accumulation.
authors.affiliation: Department of Orthopaedic Surgery, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.
authors.forename: Maxwell
authors.initials: M
authors.lastname: Langfitt
authors.forename: Lawrence X
authors.initials: LX
authors.lastname: Webb
authors.forename: Cheryl
authors.initials: C
authors.lastname: Onwuchuruba
authors.forename: Michael
authors.initials: M
authors.lastname: Callahan
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Smith
mesh_terms: D000818:Animals; D001794:Blood Pressure; D002199:Capillary Permeability; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives* / Q000494:pharmacology; D005456:Fluorescent Dyes / Q000494:pharmacology*; D008297:Male; D008833:Microcirculation; D018482:Muscle, Skeletal / Q000098:blood supply / Q000473:pathology*; D054792:Muscle, Striated / Q000473:pathology*; D054843:Negative-Pressure Wound Therapy / Q000379:methods*; D051381:Rats; D012709:Serum Albumin / Q000494:pharmacology*; D014664:Vasodilation / Q000502:physiology; D014945:Wound Healing; D014947:Wounds and Injuries / Q000473:pathology*
chemical_list: C518288:FITC-albumin; D005456:Fluorescent Dyes; D012709:Serum Albumin; D016650:Fluorescein-5-isothiocyanate