title: Periarticular tissue levels of cytokine- and endothelin-1-like immunoreactivity during the course of antigen-induced arthritis in the rat.
abstract: OBJECTIVE
  To correlate the changes in periarticular tissue levels of pro-inflammatory cytokines and endothelin-1 (ET-1) to local pathophysiology in rats with antigen-induced arthritis (AIA).
  
  
  METHODS
  The periarticular soft tissue was excised from sixty-six rats at different stages of AIA.
  
  
  METHODS
  The samples were homogenized and the levels of immune like (LI) reactivities were determined. The levels in the arthritic joints were compared to those in non-arthritic tissue. Statistical significance was determined by ANOVA followed by Fisher PLSD.
  
  
  RESULTS
  Compatible with a role in an early alarm reaction some mediators (tumor necrosis factor alpha-LI, interleukin-2-LI and interferon-gamma-LI) were elevated prior to the vascular inflammatory activity. The curve for ET-1-LI closely followed the intensity of the inflammation whereas these parameters preceeded the elevation of interleukin-1beta-LI.
  
  
  CONCLUSIONS
  Transient waves of different mediators appear during the course of the arthritis. This indicates the presence of active downregulatory mechanisms. Here the model could differ from human rheumatoid arthritis.
authors.affiliation: Department of Immunopharmacology, Preclinical R & D, Astra Draco AB, Lund, Sweden. sven.ea@telia.com
authors.forename: S E
authors.initials: SE
authors.lastname: Andersson
authors.forename: K
authors.initials: K
authors.lastname: Lexmüller
authors.forename: K
authors.initials: K
authors.lastname: Alving
authors.forename: G M
authors.initials: GM
authors.lastname: Ekström
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000378:metabolism*; D002358:Cartilage, Articular / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D019332:Endothelin-1 / Q000378:metabolism*; D005260:Female; D007371:Interferon-gamma / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D016207:Cytokines; D019332:Endothelin-1; D007375:Interleukin-1; D007376:Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma