Effects of intraperitoneal injection of TIIAS on SNL-induced pro-inflammatory cytokines and monocyte chemotactic protein (MCP-1) level in spinal dorsal horn revealed by ELISA. The levels of IL-1β, IL-6, and TNF-α were increased 10 days after SNL injury in the ipsilateral spinal dorsal horn (A1-A3, B). The lowest dosage (2 mg/kg) of TIIAS did not have any obvious effects on the expression of IL-1β, IL-6, and MCP-1 after SNL injury. However, SNL-induced elevated IL-1β, IL-6, and MCP-1 expression was reduced by the treatment of TIIAS (10 and 50 mg/kg) in a dose-dependent manner. TIIAS (2, 10, and 50 mg/kg) could down-regulate SNL-induced elevated TNF-α in a dose-dependent manner (A1-A3, B). Asterisk, number sign, or dollar sign each indicates statistically significant difference (P < 0.05) between groups, n = 4 for each group. SNL, spinal nerve ligation; TIIAS, tanshinone IIA sulfonate; Veh, vehicle; IL-1β, interleukin-1 beta.