TY - JOUR T1 - Investigation into the Potential Anti-Inflammatory Effects of Endothelin Antagonists in a Murine Model of Experimental Monosodium Urate Peritonitis JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 90 LP - 97 DO - 10.1124/jpet.104.065573 VL - 310 IS - 1 AU - Stephen J. Getting AU - Clara Di Filippo AU - Connie W. Lam AU - Francesco Rossi AU - Michele D'Amico Y1 - 2004/07/01 UR - http://jpet.aspetjournals.org/content/310/1/90.abstract N2 - Endothelin (ET)-1 has been detected in many inflammatory pathologies, including rheumatoid arthritic patients, asthma, and ischemic-reperfusion injury. In this study, we have investigated the effect of a panel of different ET-1 antagonists displaying different selectivities for the receptors in a murine model of experimental inflammatory peritonitis. Systemic treatment of mice with the ETA antagonist C33H44N6O5, N-[N-[-N(hexahydro-1H-azepin-1-yl)carbonyl]-l-leucyl]-1-methyl-d-tryptophyl]-3-(2-pyridinyl)-d-alanine (FR139317) inhibited neutrophil accumulation. However, a greater degree of inhibition was observed with the ETB antagonist C34H51N5O7, N-cis-2,6-dimethylpiperidinocarbonyl-b-tBu-Ala-d-Trp(1-methoxycarbonyl)-d-Nle-OH (BQ-788) and the ET(A and B) antagonist C52H65N7O10, N-acetyl-α-[10,11-dihydro-5H-dibenzo-[a,d]cycloheptadien-5-yl]-d-Gly-Leu-Asp-lle-lle-Trp (PD145065); all these effects occurred without altering peripheral blood cell counts. Release of the CXC chemokine KC was significantly reduced by the FR139317 and PD145065 but not by BQ-788. Evaluation of the therapeutic potential of these antagonists showed that PD145065 inhibited neutrophil migration and KC release, whereas the others caused a nonsignificant reduction in these parameters. Parameters of endothelial cell activation showed that urate-stimulated interleukin-1β release was inhibited by BQ-788 and PD145065 but not by FR139317, whereas ET-1 was only inhibited by the mixed antagonist. A different scenario was observed with respect to release of the CXC chemokine KC with FR139317 and PD145065 being effective, whereas with a marker of polymorphonuclear activation the ETA and mixed antagonist inhibited adhesion molecule expression. These data show that ET-1 antagonists elicit different mechanisms of actions in the way they display their antimigratory effects in a murine model of monosodium urate crystal peritonitis. The American Society for Pharmacology and Experimental Therapeutics ER -