title: Determination of markers for collagen type I turnover in peritendinous human tissue by microdialysis: effect of catheter types and insertion trauma.
abstract: OBJECTIVE
  Previous results from our group have shown that loading of human tendon elevates tendinous type I collagen production measured by microdialysis. However, exclusion of the observed elevation as a response to trauma from inserting the microdialysis catheters or a possible influence from the collagen production in skin was not determined.
  
  
  METHODS
  Using the microdialysis method we measured the tissue levels of type I collagen metabolism markers [procollagen I COOH-terminal propeptide (PICP) and COOH-terminal telopeptide of type I collagen (ICTP)] in peritendinous tissue of the Achilles tendon in volunteers at two time points, 0 and 72 h. Using two different catheter types, an investigation of the contribution from the skin in the collagen results obtained was also examined.
  
  
  RESULTS
  The data showed no significant changes in the dialysate levels for PICP or ICTP (p>0.05) in either of the catheters.
  
  
  CONCLUSIONS
  Inserting microdialysis fibres around the Achilles tendon twice does not increase the collagen type I metabolism determined 3 days after the initial trauma, and when using microdialysis for measuring peritendinous collagen turnover the skin contribution can be regarded as negligible. These findings support microdialysis as a valid method for the determination of collagen metabolism in peritendinous tissue.
authors.affiliation: Institute of Sports Medicine, Bispebjerg Hospital, DK-2400 Copenhagen, Denmark. olesenjens@yahoo.dk
authors.forename: J L
authors.initials: JL
authors.lastname: Olesen
authors.forename: H
authors.initials: H
authors.lastname: Langberg
authors.forename: K M
authors.initials: KM
authors.lastname: Heinemeier
authors.forename: A
authors.initials: A
authors.lastname: Flyvbjerg
authors.forename: M
authors.initials: M
authors.lastname: Kjaer
mesh_terms: D000125:Achilles Tendon / Q000378:metabolism*; D000328:Adult; D002404:Catheterization / Q000009:adverse effects*; D024042:Collagen Type I / Q000378:metabolism*; D003238:Connective Tissue / Q000378:metabolism*; D006801:Humans; D008297:Male; D017551:Microdialysis / Q000009:adverse effects*; D010446:Peptide Fragments / Q000378:metabolism; D010455:Peptides; D011347:Procollagen / Q000378:metabolism
chemical_list: D024042:Collagen Type I; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; C042813:procollagen type I carboxy terminal peptide