title: [Effects of human recombinant interleukin-1 receptor antagonist on isolated trachea smooth muscle of the guinea pig].
abstract: OBJECTIVE
  To study the effects of human recombinant interleukin-1 receptor antagonist (IL-1ra) on isolated trachea smooth muscle (TSM) of the guinea pig.
  
  
  METHODS
  Changes of the tension of isolated trachea were measured by force-displacement transducer and MedLab recording system in vitro.
  
  
  RESULTS
  IL-1ra showed direct relaxed effect on TSM in normal and ovalbumin sensitized guinea pig. The EC50 values were 8.06 x 10(-8) and 5.88 x 10(-7) mol.L-1 respectively. IL-1ra (1 x 10(-7)-1 x 10(-5) mol.L-1) concentration-dependently inhibited the contraction of TSM induced by 1 x 10(-3) mol.L-1 histamine (His), 1 x 10(-3) mol.L-1 acetylcholine (ACh) and 1 x 10(-6) mol.L-1 5-hydroxytryptamine (5-HT) (P < 0.05 or 0.01). When IL-1ra was given in advance, the contractile actions of His, ACh and 5-HT were antagonized by IL-1ra (1 x 10(-7)-1 x 10(-5) mol.L-1), the pD'2 value for His was 6.6 +/- 0.3. However, the contractile action of ACh was enhanced by IL-1ra at low concentration of 1 x 10(-9)-1 x 10(-8) mol.L-1. IL-1ra significantly prevented and inhibited the contraction of sensitized TSM induced by antigen ovalbumin, the IC50 value was 4.48 x 10(-7) mol.L-1.
  
  
  CONCLUSIONS
  The results indicate that IL-1ra, within certain concentration, can relax the normal, contracted and sensitized ISM of the guinea pig in vitro.
mesh_terms: D000818:Animals; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D053590:Interleukin 1 Receptor Antagonist Protein; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins / Q000494:pharmacology; D012795:Sialoglycoproteins / Q000494:pharmacology*; D014132:Trachea / Q000166:cytology*
chemical_list: C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins; D012795:Sialoglycoproteins