Fig. 2.

Expression and distribution of CXCL1 protein in vlPAG after BCP in rats. a Western blot analysis showing the time course of vlPAG CXCL1 expression in sham and BCP rats. CXCL1 protein upregulation was gradually increased from 6 days to 18 days. ***p < 0.001 vs. naïve group. b RT-PCR results showing the increase of CXCL1 mRNA expression in vlPAG after inoculation. CXCL1 mRNA upregulation was gradually increased from 6 days to 18 days. ***p < 0.001, **p < 0.01 vs. naïve control. c–g Immunostaining showing CXCL1-IR was increased in the spinal cord at 6 days (e), 12 days (f), and 18 days (g). h Statistical analysis of CXCL1-immunoreactive (IR) intensity further confirmed the increase of CXCL1 expression in vlPAG after BCP. ***p < 0.001 vs. naïve group. (i–k) Double staining showed CXCL1 was co-localized with astrocytic marker, GFAP (i), but not with microglial marker CD11 (j) or neuronal marker NeuN (k). n = 4. Scale bar: 100 um.Aq, aqueduct