Effect of endogenous kinins, prostanoids, and NO on kinin B1 and B2 receptor expression in the rabbit.
To determine whether kinin receptor expression is regulated by kinins, prostaglandins, and/or nitric oxide (NO), rabbits were treated with a B(1) receptor (B(1)R) antagonist, a B2 receptor (B2R) antagonist, a prostacyclin mimetic, or inhibitors of NO synthase, cyclooxygenase, or angiotensin-converting enzyme. The mRNA concentrations for B1R and B2R (multiplex RT-PCR) were measured in several organs. The B2R mRNA expression was not significantly upregulated by any of the treatments; it was notably downregulated by angiotensin-converting enzyme or cyclooxygenase blockade or B2R antagonism in the heart and duodenum. A treatment with bacterial lipopolysaccharide (LPS), known to induce B1R expression, has also been applied and was the most consistent in upregulating the expression of B1R mRNA (kidney, duodenum, and striated muscle). The contractile responses mediated by kinin receptors in blood vessels isolated from the treated rabbits also indicated that LPS was the only B1R inducer (aorta). Icatibant, a nonequilibrium antagonist of the rabbit B2R, was the sole tested drug to alter the contractions mediated by the B2R in the jugular vein or the intensity of the immunohistochemical B2R staining in several organs (inhibition in both cases). B2R mRNA expression was downregulated in some organs by several of the applied treatments, but the data did not support generally applicable feedback for the regulation of B2R expression involving endogenous kinins, prostanoids, or NO. There was no indication of compensatory or reciprocal regulation of B1Rs, relative to B2Rs, inasmuch as B1R expression was restricted to LPS-treated animals.
Marceau
F
F
Centre Hospitalier Universitaire de Québec, Centre de Recherche du Pavillon l'Hôtel-Dieu de Québec, Quebec, Canada G1R 2J6. francois.marceau@crhdg.ulaval.ca
Larrivée
J F
JF
Bouthillier
J
J
Bachvarova
M
M
Houle
S
S
Bachvarov
D R
DR
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001920:Bradykinin / Q000031:analogs & derivatives / Q000494:pharmacology; D065168:Bradykinin Receptor Antagonists; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004008:Diclofenac / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects; D004386:Duodenum / Q000187:drug effects / Q000378:metabolism; D004656:Enalapril / Q000494:pharmacology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D006321:Heart / Q000187:drug effects; D006632:Histamine / Q000494:pharmacology; D016285:Iloprost / Q000494:pharmacology; D066298:In Vitro Techniques; D007705:Kinins / Q000502:physiology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology; D009206:Myocardium / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D010656:Phenylephrine / Q000494:pharmacology; D011453:Prostaglandins / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D011817:Rabbits; D043783:Receptor, Bradykinin B1; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic / Q000187:drug effects*
D000806:Angiotensin-Converting Enzyme Inhibitors; D000894:Anti-Inflammatory Agents, Non-Steroidal; C121350:B 9858; D065168:Bradykinin Receptor Antagonists; D016861:Cyclooxygenase Inhibitors; D007705:Kinins; D008070:Lipopolysaccharides; D011453:Prostaglandins; D012333:RNA, Messenger; D043783:Receptor, Bradykinin B1; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin; D004008:Diclofenac; D010656:Phenylephrine; D009569:Nitric Oxide; D004656:Enalapril; C065679:icatibant; D006632:Histamine; D016285:Iloprost; D001920:Bradykinin; D019331:NG-Nitroarginine Methyl Ester