THE CONTRIBUTION OF PERIPHERAL BRADYKININ B-2 RECEPTORS TO CARRAGEENAN-EVOKED EDEMA AND SPINAL C-FOS EXPRESSION IN RATS

Intraplantar co-injection of HOE140 (D-Arg-[Hyp(3),Thi(5),D-Tic(7),Oic (8)]bradykinin), a selective bradykinin B-2 receptor antagonist (0.1, 1 and 10 mu g), with carrageenan dose-dependently (r = 0.66, P < 0.01) reduced the carrageenan-evoked total number of c-Fos protein-like imm unoreactive (c-Fos-LI) neurones (23 +/- 5%, 35 +/- 6% and 50 +/- 5% re duction; P < 0.01, P < 0.001 and P < 0.001, respectively). These reduc ing effects were dose-dependent for the number of c-Fos-LI neurones in both superficial (r = 0.70, P < 0.01) and deep (r = 0.53, P < 0.05) l aminae. Intraplantar co-injection of HOE140 (0.1, 1 and 10 mu g) with carrageenan significantly reduced the carrageenan-evoked paw (25 +/- 7 % 41 +/- 6% and 41 +/- 3% reduction; P < 0.001 for all) and ankle (46 +/- 6%, 61 +/- 5% and 61 +/- 5% reduction; P < 0.001 for all) oedema. Our results provide further evidence for the involvement of peripheral bradykinin B, receptors in carrageenan-induced inflammatory nocicepti ve transmission.