Effects of Nav1.7 Expression on Neuropathic Pain Induced by Oxaliplatin

Objective To investigate the effects of voltage-gated sodium channel(VGSC) Nav1.7 expression on oxaliplatin-induced neuropathic pain. Methods A total of 96 SD male mice were randomized into two groups: oxaliplatin-induced neuropathic pain(OINP) group received a single intraperitoneal oxaliplatin administration 6 mg/kg, and medium glucose injection (Vehicle) group received a single intraperitoneal injection of 5% glucose injection. 50% paw withdrawal threshold(PWT) was measured by von Frey filament when observing allodynia before administration and after administration from d1 to d10. The L3-5 dorsal root ganglions(DRG) were removed 3, 7 and 10 days after administration. Immunohistochemistry(IHC), RT-PCR and Western blot were applied to detect DRG Nav1.7and mRNA expression. Results HC analysis showed that Nav1.7 was positively expressed in DRG neurone in both groups, in brown granule, and mainly located in cytoplasm. Moreover, the difference between two groups was statistically significant(P<0.05). RT-PCR analysis showed that Nav1.7 mRNA was expressed in both groups, with no significant difference(P<0.05). Western blot analysis showed that Nav1.7 was expressed in both groups, and the level in OINP group was significantly higher than that in Vehicle group (P<0.05). Conclusion Oxaliplatin may induce the development of neuropathic pain by upregulating Nav1.7 expression in peripheral nerve.