title: Anticoagulants affect matrix metalloproteinase 9 levels in blood samples of stroke patients and healthy controls.
abstract: OBJECTIVE
  Matrix metalloproteinase-9 (MMP-9) represents a promising marker for acute stroke management. In clinical studies MMP-9 has been quantified by ELISA using differing protocols. We aimed to establish a valid protocol by evaluation of preanalytics.
  
  
  METHODS
  Blood from stroke patients (n=28) and healthy controls (n=28) was drawn into tubes containing different anticoagulants (EDTA, citrate, lithium-heparin (heparin) and heparin with proteinase inhibitors) and processed after 0, 60 and 240 min. MMP-9 plasma protein and mRNA from mononuclear leukocytes were determined.
  
  
  RESULTS
  In regard to anticoagulants used, samples showed different MMP-9 protein baseline values and kinetics. Stable MMP-9 protein concentrations were only measured from EDTA samples. Particularly in samples with proteinase inhibitors protein and mRNA concentrations increased over time. Kinetics did not differ between patients and controls.
  
  
  CONCLUSIONS
  Preanalytics plays a key role for determination of MMP-9. EDTA seems to be a valid anticoagulant for MMP-9 protein measurement.
authors.affiliation: Department of Neurology, Hannover Medical School, Carl-Neuberg-Straße 1, 30623 Hannover, Germany.
authors.forename: Munir
authors.initials: M
authors.lastname: Rababah
authors.forename: Hans
authors.initials: H
authors.lastname: Worthmann
authors.forename: Milani
authors.initials: M
authors.lastname: Deb
authors.forename: Anita B
authors.initials: AB
authors.lastname: Tryc
authors.forename: Yue Tao
authors.initials: YT
authors.lastname: Ma
authors.forename: Omnia M
authors.initials: OM
authors.lastname: El Bendary
authors.forename: Hartmut
authors.initials: H
authors.lastname: Hecker
authors.forename: Annemarie
authors.initials: A
authors.lastname: Goldbecker
authors.forename: Meike
authors.initials: M
authors.lastname: Heeren
authors.forename: Korbinian
authors.initials: K
authors.lastname: Brand
authors.forename: Karin
authors.initials: K
authors.lastname: Weissenborn
authors.forename: Ralf
authors.initials: R
authors.lastname: Lichtinghagen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000494:pharmacology; D016477:Artifacts; D001774:Blood Chemical Analysis / Q000379:methods*; D016022:Case-Control Studies; D019343:Citric Acid / Q000494:pharmacology*; D004795:Enzyme Stability; D005260:Female; D006493:Heparin / Q000494:pharmacology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000201:enzymology / Q000378:metabolism; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood* / Q000235:genetics; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018709:Statistics, Nonparametric; D020521:Stroke / Q000097:blood* / Q000201:enzymology; D014158:Transcription, Genetic
chemical_list: D000925:Anticoagulants; D012333:RNA, Messenger; D019343:Citric Acid; D006493:Heparin; D020780:Matrix Metalloproteinase 9