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目的:观察microRNA-217(miR-217)在坐骨神经部分结扎(partial sciatic nerve ligation，pSNL)大鼠的神经性疼痛及和神经炎症中的作用。方法:24只健康成年雄性SD大鼠随机分成3组：pSNL组(坐骨神经部分结扎)、Sham组(假手术组)、正常组(不进行任何处理)，每组8只。于手术前第1，2，3天以及手术后第1，3，7，14天进行机械缩足阈 (mechanical withdrawal threshold，MWT) 和热缩足潜伏期 (paw withdrawal thermal latency，PWTL)值测定。qRT-PCR实验检测大鼠手术侧脊髓组织miR-217和TLR5的mRNA表达变化。另外取24只健康成年雄性SD大鼠随机分成3组：pSNL-LV-miR-217组(坐骨神经部分结扎＋鞘内注射LV-miR-217)、pSNL- LV-NC组(坐骨神经部分结扎＋鞘内注射LV-NC)、假手术组，每组8只。于手术前第1，2，3天以及手术后第1，3，7，14天进行MWT和PWTL测定，并利用qRT-PCR实验和Western blot实验检测TLR5、COX-2、IL-6和TNF-α在大鼠脊髓组织中的表达情况。结果:痛行为结果显示，与Sham组[7 th d(13.58±0.30)g，14 th d(14.54±0.51)g]相比，pSNL组的MWT在术后第7天[(6.72±0.15)g，n t＝11.79，n P<0.05]和第14天均降低[(5.72±0.22)g，n t＝17.83，n P<0.05)，差异有统计学意义。pSNL组的PWTL在术后第7天以及第14天分别为(6.78±0.21)s 、(5.99±0.22)s，与Sham组[(14.86±0.35)s，(14.50±0.51)s]比较均降低，差异有统计学意义(n t＝4.86，7.13，均n P<0.05)。qPCR实验显示，pSNL组的大鼠脊髓中miR-217表达下调、TLR5表达上调，与假手术组相比差异有统计学意义(n t＝8.94，n P<0.01；n t＝7.54，n P<0.01)。鞘内注射miR-217后连续测定MWT和PWTL实验显示：pSNL-LV-miR-217组的MWT与pSNL-LV-NC组相比差异有统计学意义(7 th d：n t＝14.79，n P<0.01；14 th d：n t＝15.83，n P<0.01)。pSNL-LV-miR-217组的PWTL在术后第7天及第14天均明显升高(7 d：n t＝14.95，n P<0.01；14 d：n t＝16.27，n P<0.01)。qRT-PCR实验显示，与pSNL-LV-NC组相比，pSNL-LV-miR-217组的miR-217明显上升(n t＝7.49，n P<0.01)，TLR5、COX-2(n t＝8.82，n P<0.05)、IL-6(n t＝6.42，n P<0.05)和TNF-α(n t＝7.46，n P<0.05)的表达明显降低。Western blot实验显示，pSNL-LV-miR-217组的TLR5、COX-2、IL-6和TNF-α的蛋白表达在术后第7天明显降低。n 结论:鞘内注射miR-217能明显缓解坐骨神经结扎大鼠的神经性疼痛，并且可能通过调控TLR5抑制神经炎症。“,”Objective:To observe the effect of microRNA-217 (miR-217) on neuropathic pain and neuro-inflammation in rats with partial sciatic nerve ligation (pSNL).Methods:Twenty-four healthy adult male SD rats were randomly divided into three groups: pSNL group (partial sciatic nerve ligation), Sham group (Sham surgery), and normal group (no treatment) with 8 in each group. The mechanical withdrawal threshold (MWT) and paw withdrawal thermal latency (PWTL) were measured on the 1st, 2nd and 3rd day before surgery and on the 1st, 3rd, 7th and 14th day after surgery.The mRNA expression changes of miR-217 and TLR5 in the spinal cord of rats were detected by qRT-PCR. Additionally, 24 healthy adult male SD rats were randomly divided into three groups: pSNL- LV-miR-217 group (sciatic nerve part ligation + intrathecal injection of LV-miR-217), pSNL- LV-NC group (sciatic nerve part ligation + intrathecal injection of LV-NC), and Sham operation group with 8 in each group. MWT and PWTL were measured on the first, second and third day before surgery and on the 1st, 3rd, 7th, 14th day after surgery.Results:The results of pain behavior showed that the MWT of SNL group decreased significantly on the 7th day ((6.72±0.15) g, n t=11.79, n P<0.05) and the 14th day ((5.72±0.22) g,n t=17.83, n P<0.05), compared with sham group (7th d (13.58±0.30) g, 14th d (14.54±0.51)g). PWTL of pSNL group was (6.78±0.21) s and (5.99±0.22)s respectively on the 7th and 14th day after operation, which was lower than those of Sham group ((14.86±0.35) s, (14.50±0.51) s), the difference was statistically significant (n t=4.86, 7.13, both n P<0.05). The qPCR experiment showed that the expression of miR-217 was down-regulated and the expression of TLR5 was up-regulated in the spinal cord of rats in the pSNL group, showing significant differences compared with the Sham group (n t=8.94, n P<0.01;n t= 7.54, n P<0.01). The MWT of the pSNL- LV-miR-217 group were significantly increased on the 7th and 14th day after the intraoperative injection of miR-217, showing a significant difference compared with the pSNL-LV-NC group (7th d:n t=14.79, n P<0.01; 14th d:n t=15.83, n P<0.01). The PWTL of the pSNL-LV-miR-217 group were significantly increased(7th d:n t=14.95, n P<0.01; 14th d:n t=16.27, n P<0.01). qPCR assay showed that compared with the pSNL-LV-NC group, the expression of miR-217 in the pSNL-LV-miR-217 group was significantly increased (n t=7.49, n P<0.01), and the expression of TLR5, COX-2(n t=8.82, n P<0.05), IL-6(n t=6.42, n P<0.05) and TNF-α(n t=7.46, n P<0.05) was significantly decreased. Western blot assay showed that the protein expressions of TLR5, COX-2, IL-6 and TNF-α in pSNL-LV-miR-217 group were significantly decreased on the 7th day after the operation.n Conclusions:Intrathecal injection of miR-217 can significantly alleviate sciatic nerve ligation neuropathic pain and may inhibit neuroinflammation by regulating TLR5.