Fig. 2.

(A, C) Western blotting assays of GFAP, p-ERK1/2, and MOR were performed in the amygdala tissue of rats. The results show that the expression of GFAP and p-ERK1/2 are up-regulated in group S + IN. The expression of MOR is down-regulated in group S + IN. (B) Both stress and operation could increase the level of serum cortisol in rats. The level of serum cortisol in the rats of group S + IN is significantly higher than that in other groups (*P < 0.050), but there was no significant difference between group IN and group S (**P < 0.050). The error bars indicate mean ± standard deviation. GFAP: glial fibrillary acidic protein, p-ERK1/2: phosphorylated extracellular regulatory protein kinase, MOR: mu-opioid receptors, S: stress, IN: incision.