OSM induces thermal hypersensitivity depending on gp130 and TRPV1. (A) Changes in heat sensitivity following hindpaw injection of OSM in C57BL6J wildtype mice. Paw withdrawal latencies were determined at the injected (black squares) and the uninjected hindpaw (black open circles) in response to ramp-shaped heat stimuli and were significantly attenuated at all time points at the ipsilateral site compared to contralateral site (n = 10). (B) Comparison of the PWL between both gp130fl/fl and SNS-gp130-/- mice at the OSM injected hindpaw shows a significant difference; the PWL of gp130fl/fl (black squares, n = 10) are significantly shorter than those of SNS-gp130-/- (red squares, n = 13) starting after 30 minutes until 4 hours after OSM injection. (C) In contrast, the PWL in response to ramp-shaped heat stimuli applied to the plantar side of the hindpaw ipsilateral (red open circle) and contralateral (red squares) of TRPV1-/- mice (n = 11) did not significantly change after OSM injection. * p < 0.05, ** p < 0.01, *** p < 0.001, 2-way repeated ANOVA.