Leptin alleviates the neuropathic pain. The thermal withdrawl latency TWL (A) and mechanical withdrawl threshold MWT (B) were measured after intrathecal administration of leptin. Leptin was intrathecally delivered once daily for 6 days beginning 7 days after CCI, as indicated by arrows. The TWL and MWT were tested 2 h after each administration of leptin. Data are shown as mean ± S.E.M, n = 5. *P < 0.05, #P < 0.01 and @P < 0.001 vs CCI + Vehicle group.