Effects of drugs administration on SNL-induced NR1 phosphorylation. Phosphorylated NR1 (pNR1) level was much higher in SNL-Saline group than that of Sham-Saline group (* P < 0.05). Intrathecal ketamine (100 μg/kg) down-regulated pNR1 level compared with that of SNL-Saline group. Coadministration further inhibited pNR1 expression than that of individual ketamine injection. Furthermore, pNR1 returned to high level at 1 d after individual ketamine injection. However, pNR1 remained low at 1 d in the coadministration group compared with that of individual ketamine injection. Additionally, LAA application alone has no obvious effects on SNL-induced NR1 phosphorylation. *, # and $ each indicates statistically significant difference with P < 0.05 between groups.