title: Endothelium-dependent and endothelium-independent skin vasoreactivity in the elderly.
abstract: OBJECTIVE
  It was demonstrated that endothelium-dependent vasoreactivity, an aspect of endothelial functioning, is impaired in coronary and brachial arteries, and in skeletal muscle resistance vessels of elderly people. However, little data is available about the influence of aging per se on the endothelial function of the skin microcirculation. The aim of the present study was to evaluate the endothelial function and intrinsic vasodilatory capacity of the skin microcirculation in elderly people with a low atherosclerosis risk profile.
  
  
  METHODS
  Using laser Doppler flowmetry, we measured the cutaneous hyperemic responses following local iontophoresis delivery of an endothelium-dependent vasodilator, acetylcholine (ACh), and an endothelium-independent vasodilator, sodium nitroprusside (SNP), in 15 subjects older than 65 years and in 15 subjects younger than 50 years. Exclusion criteria were diabetes, hyperlipidemia, smoking, arterial hypertension and cardiovascular diseases.
  
  
  RESULTS
  Skin maximal hyperemic responses induced both by ACh and by SNP delivery did not differ between the younger and the older groups. Cutaneous blood flow progressively increased in response to the 8 ACh delivery steps, both in the older and younger groups; however, the dose-response curve following ACh delivery was significantly lower in the former (p < 0.001).
  
  
  CONCLUSIONS
  While these results should be viewed as preliminary due to the small sample size, they suggest that aging in itself is associated with a mild endothelium dysfunction in the skin microcirculation, whereas its overall vasodilatory capacity is preserved.
authors.affiliation: Department of Internal Medicine, University of Pisa, Pisa, Italy. mrossi@int.med.unipi.it
authors.forename: Marco
authors.initials: M
authors.lastname: Rossi
authors.forename: Adamasco
authors.initials: A
authors.lastname: Cupisti
authors.forename: Serena
authors.initials: S
authors.lastname: Mariani
authors.forename: Gino
authors.initials: G
authors.lastname: Santoro
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Pentimone
mesh_terms: D000109:Acetylcholine / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D004730:Endothelium, Vascular / Q000502:physiology*; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology; D009599:Nitroprusside / Q000008:administration & dosage; D012867:Skin / Q000098:blood supply*; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D014665:Vasodilator Agents; D009599:Nitroprusside; D000109:Acetylcholine