Fig. 4

CGRP receptor- and PKA-dependent effects on the CGRP-induced capsaicin-stimulated current densities in the trigeminal neurons. The trigeminal neurons were incubated with a PKA inhibitor (1 µM H89) or a CGRP receptor antagonist (100 nM BIBN4096BS) for 30 min prior to incubation with 1 µM CGRP for 4 h, and currents were evoked with 10 µM capsaicin. a The inward current responses of the trigeminal neurons evoked by 10 µM capsaicin (arrow). b The histogram summarizes the current densities (pA/pF). The results are expressed as the mean ± SEM of 13 independent records. Statistics was performed using ANOVA with Tukey–Kramer tests. **p < 0.01 compared with the control, and ^# p < 0.01 and ^## p < 0.001 compared with the CGRP-incubated neurons