Figure 2

The expressions of p-ERK1/2-IR cells, COX-2 mRNA and NK-1mRNA in spinal cord dorsal horn of rats in control group and at 6, 25 and 49 h after subcutaneous injection of CFA into the plantar hindpaw region. A-D. Immunohistochemistry shows p-ERK1/2-IR cells in the L4-6 ipsilateral spinal cord dorsal horn in control rats (A), model rats at 6 h (B), 25 h (C), and 49 h (D). E-G. Quantification of p-ERK1/2-IR cells, COX-2 mRNA and NK-1 mRNA expression in L4-6 ipsilateral spinal cord dorsal horn, respectively. Results are mean ± SEM; n = 6. *P < 0.05, **P < 0.01 versus control group at the corresponding time point. The scale bar is 100 μm.