Figure 3.

BK-induced overt nociception is dependent on TRPV1 activation. (a) Desensitization to the nociceptive effect caused by the i.pl. injection of capsaicin (CPS, 5.2 nmol paw⁻¹) or BK (10 nmol paw⁻¹). (b) Nociceptive effect caused by the coinjection of low doses of BK (0.3 nmol paw⁻¹) with capsaicin (CAP, 0.03 nmol paw⁻¹) or acidified saline (pH 5.5). Each column represents the mean±s.e.m. of 4–6 mice. The asterisks denote the significance levels. (a) ^**P<0.01, compared with the first PBS injected mice; ^##P<0.01, compared with the first BK or CPS injected mice; ⁺P<0.01, compared with the third PBS injected mice (one-way ANOVA followed by Student–Newmann–Keuls' test). (b) ^*P<0.05; ^**P<0.01, compared with the vehicle injected mice (one-way ANOVA followed by Dunnett's test).