脊髓胶质细胞在小鼠骨癌痛形成中的作用

目的 评价脊髓胶质细胞在小鼠骨癌痛形成中的作用.方法 健康雄性C3H/He小鼠40只,周龄8～10周,体重18～22 g,随机分为4组(n=10):假手术组(S组)、骨癌痛组(B组)、PBS组(P组)和米诺环素组(M组).S组跟骨骨髓腔内注射PBS 10 μl;余3组跟骨骨髓腔内注射含2×105个骨纤维肉瘤细胞的PBS 10 μl制备骨癌痛模型,于造模前即刻开始PBS组鞘内注射PBS 5μl,M组鞘内注射米诺环素(用PBS溶解为0.2 mmol/L)5μl,1次/d,连续11 d.于造模前1 d、造模后即刻、3、5、7、9、11 d时测定机械痛阈;于造模后3、7、9、11 d机械痛阈测定结束后测定冷痛阈.痛阈测定结束后处死小鼠,取脊髓组织,测定神经胶质纤维酸性蛋白(GFAP)和CD11b的表达水平.结果 与S组比较,B组和P组造模后3-11 d时、M组造模后3、5 d时机械痛阈升高,B组、P组和M组造模后7～11 d时冷痛阈升高,脊髓CD11b和GFAP表达上调(P<0.05).与B组比较,M组造模后3-11 d时机械痛阈降低,造模后7-11 d时冷痛阈降低,脊髓CD11b和GFAP表达下调(P<0.05).结论 脊髓胶质细胞(星形胶质细胞和小胶质细胞)的激活参与了小鼠骨癌痛的形成.

Role of gliocyte in spinal cord in development of bone cancer pain in mice

Objective To evaluate the role of gliocyte in the spinal cord in the development of bone cancer pain (BCP) in mice. Methods Forty male C3H/He mice aged 8-10 weeks weighing 18-22 g were randomly divided into 4 groups ( n = 10 each) : group I sham operation (group S) , group II BCP, group Ⅲ PBS and group IV minocyline (group M) . In group BCP, PBS and M, bone cancer pain was produced by injection of NCTC2472 fibrosarcoma cell suspension (2 x 105 cells) 10 μl into medullary cavity of calcaneus bone, while in group S, PBS solution 10 μl was injected instead of cancer cell suspension. In group PBS and M, PBS 5 μl and minocyline 5 μl (dissolved to 0.2 mmol/L in PBS)_were given IT immediately before cancer cell inoculation once a day for 11 consecutive days respectively. Mechanical pain threshold was measured at 1 d before cancer cell inoculation, and at 0, 3, 5, 7, 9 and 11d after cancer cell inoculation. Cold pain threshold was measured at 3, 7, 9 and 11d after cancer cell inoculation. The animals were killed after measurement of pain threshold and L4-6, segment of spinal cord was removed for determination of GFAP and CD11b expression by Western blot. Results Compared with group S, mechanical pain threshold was significantly increased at 3-11 d after cancer cell inoculation in group BCP and PBS, and at 3 and S d after cancer cell inoculation in group M, and cold pain threshold was significantly increased at 7-11 d after cancer cell inoculation, and expression of CD11b and GFAP was up-regulated in group BCP, PBS and M ( P < 0.05) . Compared with group BCP, mechanical pain threshold was significantly decreased at 3-11 d after cancer cell inoculation, cold pain threshold was significantly decreased at 7-11 d after cancer cell inoculation, and expression of CD11b and GFAP was down-regulated in group M ( P <0.05) . ConclusionThe activiton of gliocyte in the spinal cord is involved in the development of bone cancer pian in mice.