title: Effects of interleukin-1 receptor antagonist on three types of responses to interleukin-1 in rabbit isolated blood vessels.
abstract: Interleukin-1 receptor antagonist (IRA) is a secretory product of human monocytes or related cell lines that acts as a pure interleukin-1 (IL-1) antagonist in several bioassays. IRA administration was reportedly a life-saving intervention in rabbits injected with lethal doses of bacterial lipopolysaccharide (LPS). We report the inhibitory effect of IRA on three distinct types of vascular responses to IL-1 in rabbit isolated blood vessels. The rabbit isolated superior mesenteric artery, when precontracted with phenylephrine, relaxed in a sustained manner in less than 30 min following application of recombinant interleukin-1 beta (12-290 pM), and this was a prostaglandin (PG)-dependent and endothelium-independent process. IRA (human recombinant sequence; 0.9-15 nM) behaved as an antagonist of IL-1 alpha or IL-1 beta, based on the surmountability and the concentration dependence, but could only prevent the effect of IL-1, not reverse it. IRA had no direct effect on the preparation and did not influence the acute relaxing effect elicited by substance P or iloprost, a PGI2 mimetic. Exposure to IL-1 beta depressed the response to noradrenaline (NA) in several hours in rabbit aorta rings. The inhibitory effect of IL-1 beta was endothelium and prostaglandin independent, but was prevented by a treatment with NG-nitro-L-arginine (a nitric oxide synthesis inhibitor), cycloheximide, dexamethasone, or IRA. Using the residual NA-induced contraction as a quantification of the IL-1 agonist effect, IRA was a very potent antagonist of IL-1 beta but was not totally surmountable.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Centre de Recherche, Hôtel-Dieu de Québec, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Petitclerc
authors.forename: S
authors.initials: S
authors.lastname: Abel
authors.forename: D
authors.initials: D
authors.lastname: deBlois
authors.forename: P E
authors.initials: PE
authors.lastname: Poubelle
authors.forename: F
authors.initials: F
authors.lastname: Marceau
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000187:drug effects; D001920:Bradykinin / Q000031:analogs & derivatives* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D016285:Iloprost / Q000494:pharmacology; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000494:pharmacology*; D008638:Mesenteric Arteries / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011506:Proteins / Q000494:pharmacology*; D011817:Rabbits; D011971:Receptors, Immunologic / Q000037:antagonists & inhibitors*; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins / Q000494:pharmacology; D012795:Sialoglycoproteins; D013373:Substance P / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*; D014664:Vasodilation / Q000187:drug effects*
chemical_list: C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D011506:Proteins; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins; D012795:Sialoglycoproteins; C024626:bradykinin, des-Arg(9)-; D010656:Phenylephrine; D013373:Substance P; D016285:Iloprost; D001920:Bradykinin; D009638:Norepinephrine