Bradykinin is involved in hyperalgesia induced by Bothrops jararaca venom

Bradykinin is involved in hyperalgesia (pain hypersensitivity) induced by Bothrops jararaca venom-intraplantar injection of B. jararaca venom (5 mug/paw) in rats caused hyperalgesia, which peaked 1 h after venom injection. This phenomenon was not modified by promethazine, (H-1 receptor antagonist), methysergide (5-HT receptor antagonist), guanethidine (sympathetic function inhibitor), anti-TNF-alpha or anti-interleukin-1 antibodies or by the chelating agent CaNa(2)EDTA. Venom-induced hyperalgesia was blocked by the bradykinin B-2 receptor antagonist HOE 140. On the other hand, des-Arg(9), [Leu(8)]-bradykinin, a bradykinin B-1 receptor antagonist, did not modify the hyperalgesic response. These results suggest that bradykinin, acting on B-2 receptor, is a mediator of hyperalgesia induced by B. jararaca venom. (C) 2002 Elsevier Science Ltd. All rights reserved.