Fig. 7.

Capsazepine pretreatment antagonizes the protective effect of capsaicin on ACh release at high frequencies. EPCs were measured for EDL nerve-muscle preparations isolated from control, + CAP + BoNT/A, and + capsazepine (CPZ) + CAP + BoNT/A injected mice; stimulus frequencies were 20 (A), 50 (B), and 70 (C) Hz. Numbers of mice and end-plates studied in these experiments are indicated in Table 2. D is a Western blot for TRPV1 probed with anti-rabbit TRPV1 antibody in mouse hemidiaphragm at 90 min after treatment with capsaicin alone or with BoNT/A and capsaicin.