脊髓背角星形胶质细胞NF-κB在紫杉醇诱发大鼠神经病理性痛中的作用

Role of NF-κB in astrocytes in spinal dorsal horn in a rat model of neuropathic pain induced by paclitaxel

目的评价脊髓背角星形胶质细胞NF-κB紫杉醇诱发大鼠神经病理性痛中的作用。方法健康雄性sD大鼠20只，6周龄，体重180—200g，采用随机数字表法，将其随机分为2组（n=10）：对照组（C组）和神经病理性痛组（NP组）。NP组隔日腹腔注射紫杉醇2mg/kg，共4次；对照组隔日腹腔注射生理盐水1ml／kg，共4次。于给药前和给药结束后1、7、14d时分别测定体重、机械痛阈和热痛阈。给药结束后14d时，处死大鼠，取L4-6脊髓组织，采用免疫荧光法测定脊髓背角星形胶质细胞NF-κB p65的表达。结果两组体重比较差异无统计学意义（P〉0．05）。与C组比较，NP组给药结束后7和14d时机械痛阈和热痛阈降低，脊髓背角星形胶质细胞NF-κB p65表达上调（P〈0．05或O．01）。结论紫杉醇通过激活脊髓星形胶质细胞中的NF-κB，诱发大鼠神经病理性痛。

Objective To evaluate the role of NF-κB in astrocytes in the spinal dorsal horn in a rat model of neuropathic pain induced by paclitaxel. Methods Twenty 6 year old male SD rats weighing 180-200 g were randomly divided into 2 groups （ n = 10） ： control group （group C） and neuropathie pain group （group NP）. Neuropathic pain was induced by intraperitoneal injection paclitaxel of 2 mg/kg every other day for 4 times in group NP. While the equal volume of normal saline was given instead of paclitaxel in group C. Body weight, mechanical pain threshold and heat pain threshold were determined before and at 1, 7, 14 d after administration. The animals were sacrificed and the spinal dorsal horn were removed for determination of NF-κB p65 expression in astrocytes by im- munofluorescence analysis at 14 d after administration. Results There was no significant difference in body weight between the two groups（ P 〉 0.05）. Compared with group C, mechanical pain threshold and heat pain threshold were significantly decreased 7 and 14 d after administration, the expression of NF-κB p65 in astrocytes in the spinal dorsal horn was up-regulated in group NP（ P 〈 0.05 or 0.01 ）. Conclusion Activation of NF-κB in astrocytes in the spinal dorsal horn may play an important role in neuropathic pain induced by paclitaxel in rats.