Fig. 4

PK system activation in DRG. a Representative images of PK2 immunofluorescence signal in DRG sections of CTR, BTZ 14 days, BTZ 28 days, and PC1 (BTZ + PC1) mice. Quantitative analysis of PK2 signal (b) was computed as integrated optical density for arbitrary areas (6 sections per animal, 5 animals per group). One-way ANOVA was used for statistical evaluation, followed by Bonferroni’s test for multiple comparisons. *p < 0.05, ***p < 0.001 vs CTR; °°°p < 0.001 vs BTZ day 28. c, d mRNA levels of PK-R1 and PK-R2 respectively, measured by real-time qPCR, 14 days after the first BTZ administration (c.d. 2.4 mg/kg) in CTR and BTZ mice and at the end of the BTZ protocol (c.d. 4,8 mg/kg) in CTR, BTZ, and BTZ + PC1. mRNA levels, determined by real-time qPCR, were expressed in relation to GAPDH and presented as fold increases over the levels of CTR animals (at the same time point). Data represent mean ± SD of 6 mice/group. At day 14, statistical analysis was performed by means of t test while at day 28 by one-way ANOVA followed by Bonferroni’s post-test. ***p < 0.001 vs vehicle/CTR (at the same time point); °°p < 0.01 vs BTZ day 28