fr-173657 and Dermatitis

Peptide and non-peptide kinin receptor antagonists were evaluated in cutaneous inflammation models in mice. Topical and i.p. application of kinin B(1) and B(2) receptor antagonists caused a significant inhibition of the capsaicin-induced cutaneous neurogenic inflammatory response. The calculated mean ID(50) for Hoe140 and SSR240612 were 23.83 (9.14-62.14) nmol/kg and 0.23 (0.15-0.36) mg/ear, respectively. The I(max) observed for Hoe140, SSR240612, R-715, FR173657, and FR plus SSR were 61+/-5%, 56+/-3%, 65+/-10%, 48+/-8%, and 52+/-4%, respectively. Supporting these results, double B(1) and B(2) kinin receptors knockout mice showed a significant inhibition of capsaicin-induced ear oedema (42+/-7%). However, mice with a single deletion of either B(1) or B(2) receptors exhibited no change in their capsaicin responses. In contrast, all of the examined kinin receptor antagonists were unable to inhibit the oedema induced by TPA and the results from knockout mice confirmed the lack of kinin receptor signaling in this model. These findings show that kinin receptors are present in the skin and that both kinin receptors seem to be important in the neurogenic inflammatory response. Moreover, non-peptide antagonists were very effective in reducing skin inflammation when topically applied, thereby suggesting that they could be useful tools in the treatment of some skin inflammatory diseases.

Topics: Animals; Bradykinin B1 Receptor Antagonists; Bradykinin B2 Receptor Antagonists; Capsaicin; Dermatitis; Dioxoles; Female; Male; Mice; Mice, Knockout; Quinolines; Receptor, Bradykinin B1; Receptor, Bradykinin B2; Sulfonamides

The non-peptide B2 receptor antagonist (E)-3-(6-acetamido-3-pyridyl)-N-[N-[2,4-dichloro-3-[(2-methyl-8-quinolin yl)oxymethyl]phenyl]-N-methylaminocarbonylmethyl]acrylamide (FR173657) was compared to the peptide antagonist icatibant in models of visceral and cutaneous inflammation.. Pancreatitis was induced by caerulein in anaesthetized Sprague-Dawley rats. Acute cystitis was induced by intravesical instillation of xylene or i.p. cyclophosphamide injection. Cutaneous inflammation was induced in anaesthetized guinea-pigs by s.c. injection of collagenase from Clostridium histolyticum.. FR173657 inhibited oedema formation and tissue enzyme retention during pancreatitis at 500 nmol/kg and above after peroral administration, and from 30 nmol/kg after s.c. injection; icatibant was effective at 3 nmol/kg s. c. Protein extravasation in both cystitis models was abolished by s.c. FR173657 at 300 nmol/kg. Collagenase-induced oedema was attenuated equieffectively by FR173657 and icatibant at doses of 10 micomol/kg and 300 nmol/kg s.c., respectively.. FR173657 inhibits kinin-mediated effects in visceral and cutaneous inflammation at doses that are about 10 times higher than those of icatibant. However, FR173657 is also active following oral administration.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Blood Proteins; Bradykinin Receptor Antagonists; Capillary Permeability; Cystitis; Dermatitis; Dose-Response Relationship, Drug; Female; Guinea Pigs; Pancreatitis; Quinolines; Rats; Rats, Sprague-Dawley; Receptor, Bradykinin B2