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The analgesic effect of venlafaxine (VLX), which is a selective serotonin and noradrenaline reuptake inhibitor (SNRI), has been observed on oxaliplatin-induced neuropathic pain in mice. Significant allodynia was shown after oxaliplatin treatment (6 mg/kg, i.p.), acetone and von Frey hair tests were used to assess cold and mechanical allodynia, respectively. Intraperitoneal administration of VLX at 40 and 60 mg/kg, but not 10 mg/kg, significantly alleviated these allodynia. Noradrenaline depletion by pretreatment of N-(2-Chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4, 50 mg/kg, i.p.) blocked the relieving effect of VLX (40 mg/kg, i.p.) on cold and mechanical allodynia. However, serotonin depletion by three consecutive pretreatments of para-chlorophenylalanine (PCPA, 150 mg/kg/day, i.p.) only blocked the effect of VLX on mechanical allodynia. In cold allodynia, the &alpha, 2-adrenergic antagonist idazoxan (10 &mu, g, i.t.), but not the &alpha, 1-adrenergic antagonist prazosin (10 &mu, g, i.t.), abolished VLX-induced analgesia. Furthermore, idazoxan and 5-HT3 receptor antagonist bemesetron (MDL-72222, 15 &mu, g, i.t.), but not prazosin or mixed 5-HT1, 2 receptor antagonist methysergide (10 &mu, g, i.t.), abolished VLX-induced analgesia in mechanical allodynia. In conclusion, 40 mg/kg of VLX treatment has a potent relieving effect against oxaliplatin-induced neuropathic pain, and &alpha, 2-adrenergic receptor, and both &alpha, 2-adrenergic and 5-HT3 receptors are involved in this effect of VLX on cold and mechanical allodynia, respectively.