【Objective】 To investigate the roles of AMPA receptors and NMDA receptors in the mechanism of leptin involved in neuropathic pain. 【Methods】 The effect of leptin on AMPA receptors and NMDA receptors induced-currents were record by whole-cell clamp recording in dorsal horn laminaⅡ neurons of adult SD rats. Mechanical allodynia and thermal hyperalgesia were measured on day 1

3

7

and 14 after intrathecal injection of leptin (50 μg) in naive rats

given once daily for 14 days. On day 14

all the rats were killed and the expression of AMPA receptors and NMDA receptors were measured.【Results】 Leptin dose-dependently enhanced NMDA-induced current

among which 100 nmol/L concentration had the maximal enhancement effect. Leptin had no effect on AMPA-induced current. Intrathecal injection of leptin (50 μg) in naive rats induced mechanical allodynia and thermal hyperalgesia on day 14. The behavioral changes were prevented and reversed by NMDA receptor antagonist MK-801. Moreover

intrathecal injection of leptin increased the expression of NMDA receptors subunit NR1 on dorsal horn

which was also blocked by MK-801 but had no effect on AMPA receptors subunit GluR1. 【Conclusion】 Leptin may involved the mechanisms of neuropathic pain through NMDA receptors.