title: Influence of acetylsalicylic acid (Aspirin) on cutaneous microcirculation.
abstract: BACKGROUND
  The protective effect of acetylsalicylic acid (aspirin) in primary and secondary prophylaxis of cardiovascular events is attributed to the inhibition of platelet cyclooxygenase (COX). However, a recent animal study found a vasodilating and blood pressure lowering effect of aspirin independent of COX, but mediated by inhibition of the RhoA/Rho kinase signaling pathway.
  
  
  METHODS
  Prospective, randomized, double-blind, placebo-controlled cross-over study. In each instance 5 healthy volunteers received either aspirin 500 mg/d or placebo for 7 days. Capillary red blood cell velocity (vRBC) at rest and after postischemic hyperemia was determined on day 1 and 7 by means of nailfold capillary microscopy.
  
  
  RESULTS
  In the aspirin group after 7 days a significant increase of vRBC was found at rest and during hyperemia. In the placebo group vRBC did not change. The finding was confirmed by the cross-over design of the study.
  
  
  CONCLUSIONS
  Aspirin at a dosage of 500 mg/d has an impact on vasoregulation in the microcirculation. At present, the underlying mode of action in humans is unknown.
authors.affiliation: Asklepios Klinik Harburg, 1st Medical Department, Cardiology, Hamburg, Germany. b.leithaeuser@asklepios.com
authors.forename: B
authors.initials: B
authors.lastname: Leithäuser
authors.forename: C
authors.initials: C
authors.lastname: Mrowietz
authors.forename: J-W
authors.initials: JW
authors.lastname: Park
authors.forename: F
authors.initials: F
authors.lastname: Jung
mesh_terms: D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D001783:Blood Flow Velocity; D002465:Cell Movement / Q000187:drug effects; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004912:Erythrocytes / Q000187:drug effects; D006801:Humans; D008833:Microcirculation / Q000187:drug effects*; D009262:Nails / Q000098:blood supply* / Q000187:drug effects
chemical_list: D001241:Aspirin