Fig. 1

Complete Freund’s adjuvant (CFA) upregulates Apoe protein expression in the spinal dorsal horn. A Paw withdrawal latency (PWL) to thermal stimulation in mice after physiological saline or CFA treatment. N = 6–16 mice/group. **p < 0.01, ****p < 0.0001 versus the saline-treated mice by two-way analysis of variance (ANOVA) followed by post hoc Tukey test. B–C Representative blots and quantification of Apoe expression in the ipsilateral (A) and contralateral spinal dorsal horns (B) after saline or CFA treatment. N = 4–5 mice/group. ^##p = 0.001 compared with saline-treated mice (two-tailed unpaired Student’s t-test). ^*p = 0.0117, ^**p = 0.0020 compared with saline-treated mice (one-way ANOVA, followed by Tukey’s post-hoc test). D–F Immunofluorescence staining (C) and quantification (D, E) of Apoe in the ipsilateral (Ipsi; E) and contralateral (Contra; F) spinal dorsal horns on day 1 post-saline or CFA treatment. N = 15 sections from 3 mice per group. The individual dot indicates one value from one section. All dots in one cluster present all values from one mouse. ^**p = 0.003 compared with saline-treated mice (two-tailed unpaired Student’s t-test). Bar: 100 μm. G–H Colocalization of Apoe with GFAP and Pearson correlation coefficients (r) between Apoe staining and GFAP staining. N = 26 sections from 3 mice per group. Bar: 50 μm. I The mRNA level of Apoe in the spinal dorsal horn on day 1 post-saline or CFA treatment. N = 4 mice/group. Two-tailed unpaired Student’s t-test