title: Plasma MMP-9 - a marker of carotid plaque instability.
abstract: OBJECTIVE
  to investigate whether peripheral blood levels of matrix metalloproteinases (MMPs) or their inhibitors are altered in patients with particulate cerebral embolisation.
  
  
  METHODS
  a prospective study.
  
  
  METHODS
  using sandwich enzyme immunoassay, plasma levels of MMPs-1, -2, -3 and -9, plus TIMPs-1 and -2 were quantified in 70 consecutive patients undergoing carotid endarterectomy. Patients were monitored with transcranial Doppler (TCD) preoperatively and during the dissection phase of the operation to detect those with spontaneous particulate embolisation (n =21).
  
  
  RESULTS
  the plasma level of MMP-9 was significantly higher in those patients with evidence of spontaneous embolisation compared to those without. There were no differences in other MMP levels, or plasma concentrations of TIMPs.
  
  
  CONCLUSIONS
  plasma MMP-9 levels are elevated in patients with particulate cerebral embolisation, and this may represent a novel marker of atherosclerotic plaque instability.
authors.affiliation: Department of Surgery, RKCSB, Royal Infirmary, PO Box 65, Leicester University, Leicester LE2 7LX, U.K.
authors.forename: I M
authors.initials: IM
authors.lastname: Loftus
authors.forename: A R
authors.initials: AR
authors.lastname: Naylor
authors.forename: P R
authors.initials: PR
authors.lastname: Bell
authors.forename: M M
authors.initials: MM
authors.lastname: Thompson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000201:enzymology; D005260:Female; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis* / Q000201:enzymology; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D008875:Middle Aged; D012307:Risk Factors; D012680:Sensitivity and Specificity; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D015415:Biomarkers; D020780:Matrix Metalloproteinase 9