Figure 5

Immunofluorescence staining (A) and quantification of the expression of GFAP (B) in astrocytes of the spinal dorsal horn (SDH). Low immunoreactivity was observed in the sham rats (group S). SNL (group L) increased the immunoreactivity of GFAP-positive astrocytes in the SDH. Intra-peritoneal treatment with amitriptyline (group A) had no effect on decreasing the SNL-induced activation of astrocytes. Intrathecal pretreatment in combination with intra-peritoneal administration of amitriptyline (group P) decreased the activation of astrocytes for 2 weeks (group P vs. L). Scale bars = 200 μm. Data represent mean ± SE, the Mann–Whitney U test was used for statistical comparison. (n = 24/group, 4-5/each time point). *p < 0.05, ns: not significant. POD: postoperative day; S: Sham; L: Ligation; A: post-injury intra-peritoneal amitriptyline; P: Pretreatment with intrathecal amitriptyline in addition to post-injury intra-peritoneal amitriptyline.