Fig. 8.

Effects of the specific α7-nicotinic acetylcholine receptor (α7-nAChR) antagonist methyllycaconitine (a–c) and CRF receptor antagonist α-helical CRF (9-41) (d) on cinobufagin-, PHA-543613-, or ouabain-induced mechanical antiallodynia in the rat model of bone cancer pain. Female bone cancer pain rats, approximately 3 weeks after cancer cell inoculation, received intrathecal injection of the vehicle (10 μL), methyllycaconitine (10 μg) or α-helical CRF (9-41) (20 μg) 0.5 h later followed by cinobufagin (30 μg), PHA-543613 (12 μg), or ouabain (2.5 μg), and mechanical thresholds in both the contralateral and ipsilateral hindpaws were measured by using electric von Frey filaments. The data are presented as means ± SEM (n = 6 per group). The asterisk denotes statistical significance (p < 0.05) compared to the vehicle control group, by repeated-measured two-way ANOVA followed by the post hoc Student–Newman–Keuls test