CBD3074通过促进CRMP2/NR2B复合物解偶联改善神经病理性疼痛

CBD3074 alleviates neuropathic pain by promoting the uncoupling of CRMP2/NR2B complex

摘要:

目的 观察鞘内注射CBD3074对保留性坐骨神经损伤（spared nerve injury, SNI）所致的神经病理性疼痛大鼠的镇痛作用，并从CRMP2/NR2B复合物角度初步探究其机制。 方法 ①雄性SD大鼠鞘内置管成功后，制备SNI模型；SNI术后第七天分别鞘内注射CBD3074 0.1 μg/kg、0.3 μg/kg、0.9 μg/kg、2.7 μg/kg；行为学检测各组动物SNI术前（Pre）、给药前（Post/0h）、给药后0.5h、1h、2h、3h、4h、5h、6h、12h、24h的机械痛阈值。②SNI术后第七天鞘内注射CBD3074 0.3 μg/kg；给药后2h取各组动物损伤侧L3-L6背根神经节（dorsal root ganglion, DRG）；免疫共沉淀法检测CRMP2/NR2B复合物含量；Western blot检测总NR2B、膜NR2B、iNOS的蛋白表达；生化试剂盒检测Ca2+、NO的含量。 结果 ①CBD3074各剂量均在给药后1h起效，2h左右镇痛作用达峰值；0.1和0.3 μg/kg的镇痛效果在给药后6h开始降低，0.9和2.7 μg/kg在给药后12h开始降低；ED50为0.7108 μg/kg。②CBD3074显著抑制SNI诱导的CRMP2/NR2B复合物增多，膜NR2B、iNOS蛋白水平上调，Ca2+、NO含量增多。 结论 鞘内注射CBD3074能有效缓解SNI诱导的神经病理性疼痛，其镇痛机制可能与促进CRMP2/NR2B复合物解偶联，降低CRMP2/NR2B复合物的含量有关。

Abstract:

Aim To observe the analgesic effect of intrathecal injection of CBD3074 on neuropathic pain induced by spared nerve injury (SNI) in rats, and to explore its mechanism from the perspective of CRMP2/NR2B complex. Methods ①After successful indwelling intrathecal catheters of male SD rats, an SNI model was prepared. On the seventh day after SNI, CBD3074 were injected intrathecally at 0.1 μg/kg, 0.3 μg/kg, 0.9 μg, 2.7 μg/kg. Observe the paw withdraw mechanical threshold of each group before SNI (Pre), before administration (Post/0h), 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 12h, 24h after administration. ②Intrathecal injection of CBD3074 0.3 μg/kg on the seventh day after SNI; L3-L6 dorsal root ganglion (DRG) on the injured side of each group was taken 2 hours after administration; Co-immunoprecipitation method was used to detect the content of CRMP2/NR2B complex; Western blot was used to detect the protein expression of total NR2B, surface NR2B, and iNOS; the biochemical kit was used to detect the content of Ca2+ and NO. Results ①All doses are effective 1h after administration, and the analgesic effect reaches the peak about 2h. The analgesic effects of 0.1 and 0.3 μg/kg begin to decrease at 6h after administration, and 0.9 and 2.7 μg/kg at 12h. ②CBD3074 significantly inhibited SNI-induced the increase of CRMP2/NR2B complex, the up-regulation of surface NR2B and iNOS protein levels, and the increase of Ca2+ and NO content. Conclusions Intrathecal injection of CBD3074 can effectively relieve SNI-induced neuropathic pain, and its analgesic mechanism may be related to promoting the uncoupling of CRMP2/NR2B complex and reducing the content of CRMP2/NR2B complex.