title: Noninvasive assessment of endothelial function in the skin microcirculation.
abstract: BACKGROUND
  The structure and function of blood vessels varies along the vascular tree. Endothelial dysfunction is a hallmark of increased cardiovascular (CV) risk that can be assessed by several methods, some of which are invasive and of restricted application. The aim of this study was to determine whether the laser Doppler response of skin microcirculation to acetylcholine, reflects that of conduit artery assessed by brachial artery flow-mediated dilation (FMD).
  
  
  METHODS
  Noninvasive measurement of endothelium-dependent vasodilation in the skin microcirculation by laser Doppler flowmetry (LDF) in response to a local transdermal iontophoretic application of acetylcholine (Ach-SkBF) is an operator-independent method. Ach-SkBF and FMD were measured in the nondominant upper limb of 55 unselected consecutive patients admitted in our department for evaluation of CV risk factors.
  
  
  RESULTS
  Ach-SkBF was (mean +/- s.d. (min-max)) 490 +/- 414%, (10-1667%) and FMD was 3.77 +/- 3.01% (0.91-10.91). A strong linear relationship was found between Ach-SkBF and FMD: Ach-SkBF = 122.7 FMD + 25.8 (r = 0.92, P < 0.0001).
  
  
  CONCLUSIONS
  Endothelial dilatory response to increased blood flow and to acetylcholine are similar in large arteries and in the skin microvasculature. Thus, measurement of blood flow changes in the skin microcirculation using LDF coupled with acetylcholine iontophoresis represents a technically challenging and reliable noninvasive method for the assessment of endothelial function within a large range of normal and altered endothelium responses.
authors.affiliation: Department of Non-Invasive Investigations, Cardiovascular Research Centre, PARCC Inserm U970, Lariboisière Hospital, Paris, France.
authors.forename: Haythem
authors.initials: H
authors.lastname: Debbabi
authors.forename: Philippe
authors.initials: P
authors.lastname: Bonnin
authors.forename: Pierre Henri
authors.initials: PH
authors.lastname: Ducluzeau
authors.forename: Georges
authors.initials: G
authors.lastname: Lefthériotis
authors.forename: Bernard I
authors.initials: BI
authors.lastname: Levy
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000328:Adult; D001916:Brachial Artery / Q000502:physiology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology*; D005260:Female; D006801:Humans; D007478:Iontophoresis / Q000379:methods*; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology*; D008875:Middle Aged; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D012867:Skin / Q000098:blood supply*; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014665:Vasodilator Agents; D000109:Acetylcholine