Figure 2

Involvement of PRIPs in the pain-related behavior. (A, B) Expression of PRIP-1 and PRIP-2 in the spinal cord of PRIP-1 KD, PRIP-2 KD and DKD mice 3 days after intrathecal siRNA injection. Immunoblot analyses were conducted using anti-PRIP-1 (A) and anti-PRIP-2 (B) antibodies. HVJ-envelope (HVJ-E) or scrambled siRNA (SC) was used as a negative control. For each, a representative image is shown in the upper panel. The level of immunoreactivity was normalized to β-tubulin and represented as % induction compared with the values of untreated mice (control) (means ± S.E.M., n = 4). *P < 0.05, † P < 0.05, ‡P < 0.05, §P < 0.05 and ¶P < 0.05 compared with the corresponding values in untreated, SC, HVJ-E, PRIP-1 KD, and PRIP-2 KD mice, respectively (Tukey-Kramer test). (C) Influence on pain sensitivity by the suppression of the PRIP gene using intrathecal siRNA injection in mice. Paw withdrawal threshold was measured the day before (open column) and 3 days after (closed column) injection. Values represent withdrawal threshold (mean ± S.E.M., n = 5–10). **P < 0.01 compared with the corresponding values from before injection (Student’s t-test). (D, E) Influence on pain sensitivity by the suppression of the PRIP gene in PSNL-operated mice. Paw withdrawal threshold of both contralateral (D) and ipsilateral (E) sides were measured each day after the intrathecal siRNA injection (day 0). The values before the PSNL surgery represent as “naive.” Lines used in graphs are as follows: green, violet, blue, black, and red are for PRIP-1 KD, PRIP-2 KD, DKD, HVJ-envelope, and scrambled siRNA-injected mice, respectively. Values represent withdrawal threshold (mean ± S.E.M., n = 7). *P < 0.05 compared with the corresponding values of untreated mice (day 0) (Dunnet test).