脊髓IL-1β和TNF-α在胶质细胞活化诱发小鼠骨癌痛中的作用

Role of IL-1β and TNFα in the spinal cord in a murine model of bone cancer pain reduced by activation of glial cells

目的 评价脊髓IL-1β和TNF-α在胶质细胞活化诱发小鼠骨癌痛中的作用.方法 雄性C3H/He小鼠360只,8～10周,体重18～22 g,随机分为6组（n=60）：对照组（C组）、假手术组（S组）、骨癌痛＋5μl人工脑脊液组（BCP组）、骨癌痛＋0.5 nmol氟代柠檬酸组（FC组）、骨癌痛＋16μg米诺四环素组（MI组）和骨癌痛＋0.25 nmol FC＋8 μg MI组（FC＋MI组）.S组左侧跟骨骨髓腔内仅注入10 μl α-MEN;BCP组、FC组、MI组和FC＋MI组注入含有2×105个肿瘤细胞的10 μl α-MEN制备小鼠骨癌痛模型,各组于注射肿瘤细胞前即刻及注射后分别每天定时鞘内注射人工脑脊液、氟代柠檬酸、米诺四环素、氟代柠檬酸＋米诺四环素1次,连续21 d.分别于注射肿瘤细胞前0.5 h（T0）、注射后3、5、7、10、14、21 d（T1-6）时采用von Frey细丝刺激足底测定机械痛阈,于T0,1,3,5,6时各组随机取12只小鼠处死取脊髓,采用ELISA法检测IL-1β和TNF-α的含量.结果 与T0时和C组比较,BCP组、FC组、MI组和Fc＋MI组L1-6时机械痛阈降低,T1,3,5,6时IL-1β、T5,6时,TNF-α含量升高（P〈0.05）;与BCP组比较,MI组和FC＋MI组T1-6时、FC组T4-6时机械痛阈升高,MI组和FC＋MI组T1,3,5,6时、FC组T5,6时IL-1β含量降低,FC组、MI组和FC＋MI组T5,6时TNF-α含量降低（P〈0.05）.结论 脊髓IL-lβ和TNF-α参与了胶质细胞活化诱发小鼠骨癌痛的过程.

Objeetlve To evaluate the role of IL-1β and TNF-α in the spinal cord in a murine model of bone cancer pain（BCP）induced by activation of glial cells.Methods Three hundred and sixty male 8-10 weeks old C3H/He mice weighing 18-22 g were randomly divided into 6 groups（n=60 each）：group I nomal control （group N）;group Ⅱ sham operation （group S）;group Ⅲ BCP＋aCSF（group aCSF）;group Ⅳ BCP＋FC （group FC）;group V BCP＋MI（group MI） and group Ⅵ BCP＋FC＋MI （group FC-MI）.BCP was produced by inieeting fibrosarcoma cells of bone into the medullary cavity of left ealcaneus bone.Intrathecal catheter was placed in the 4 BCP groups（group Ⅲ-Ⅳ）.FC 0.5 nmol/5 μl or/and MI 16 μg/5 μl were injected IT once a day for 21 consecutive days after operation.The mechanical threshold to von Frey filaments was measured at 0.5 h（T0）before injection of fibrosarcoma cells and at 3,5,7,10,14,21 d（T1-6）after injection of fibrosarcoma cells.Twelve animals of each group were killed and L4.5 segment of the spinal cord was removed at T0,1,3,5,6 for determination of IL-1β and TNF-α content （by ELISA） and expression （by immuno-flurorescence） in the spinal cord. Results The mechanical threshold was significantly decreased at T1-6, while IL-1β content at T1,3,5,6 and TNF-α content at T5,6 was significantly increased in group BCP, FC, MI and FC ＋ MI compared with those at T0 and group C （P 〈 0.05）. Compared with group BCP, the mechanical threshold was significantly increased at T1-6 in group MI and FC ＋ MI and at T4-6 in group FC, IL-1β content was significantly decreased at Ts,3,5,6 in group MI and FC ＋ MI and at T5,6 in group FC and TNF-α content was significantly decreased at T5,6 in group FC, MI and FC ＋ MI （ P 〈 0.05）. Conclusion IL-1β and TNF-α in the spinal cord is involved in the process of glial cell activation-induced BCP.