目的 探讨钙/钙调蛋白依赖性蛋白激酶Ⅱ(CaMKⅡ)在骨癌痛发病机制中的作用.方法 雄性C3H/HeN小鼠40只分为5组:假手对照Sham组(S组n=8),癌痛模型对照Control组(C组n=8)和KN93 Treat组(T1组n=8、T2组n=8、T3组n=8).C组和T组(T1、T2、T3)小鼠左侧股骨远端骨髓腔接种溶于α-MEM的NCTC 2472纤维肉瘤细胞,建立骨癌痛模型;S组小鼠骨髓腔注入不含NCTC 2472细胞的α-MEM.在术后的第14天S组和C组鞘内注射20%DMSO 5μl,T1、T2、T3组分别鞘内注射溶于20%DMSO的KN93 15 nmol/5μl、30nmol/5μl、60nmol/5μl.各组于给药前及给药后的0.5 h、2h、4h、8 h检测小鼠的自发抬足次数、机械性缩足反射阈值(PWMT)和热缩足反射潜伏期(PWTL).结果 鞘内给予KN9315 nmol对骨癌痛小鼠痛行为无影响,鞘内给予KN93 30nmol、60nmol能剂量依赖性减轻小鼠痛行为反应,给药后0.5 h 2组小鼠自发抬足次数[(7.25±1.49)次、(4.12±1.36)次]比C组[(11.62±1.92)次]降低,PWMT[(1.28±0.14)g、(1.75+0.46)g]、PWTL[(14.64±2.12)s、(16.85±1.61)s]比C组[(0.47±0.16)g、(11.32±1.68)s]升高,差异有显著性(P<0.05).作用2h达到高峰,维持到4h左右,8 h后基本消失.结论 CaMKⅡ在骨癌痛的发病中起重要作用,鞘内注射KN93能够剂量依赖性改善骨癌痛小鼠的痛行为.
Objective To investigate the role of Ca2+/calmodulin-dependent protein kinase Ⅱ on pain behavior in a mouse model of bone cancer pain. Methods 40 male C3H/HeN mice were divided randomly into 5 groups:sham group (S group, n=8) ,control group (C group, n=8) and KN93 treat group (T1, n=8;T2, n=8;T3, n = 8 ). Group C and T were induced mouse models of bone cancer pain by intra-left-femur inoculations of osteolytic NCTC2472 cells while group S were injected only α-MEM. On the 14 d after inoculations,group S and C received intrathecal injection of 20% DMSO 5 μl . While group T1, T2, T3 received intrathecal injection of KN93 15nmol,30nmol,60nmol which dissolved in 5 μl 20% DMSO respectively. Mice received pain behavior tests including quantification of spontaneous flinches, paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) before and at 0.5 h,2 h,4 h,8 h after administration. Results Treatment with KN93(15 nmol) have no effect on bone cancer pain,while treatment with KN93(30 nmol,60 nmol) can dose-dependently reverse quantification of spontaneous flinches, mechanical allodynia and thermal hyperalgesia which were induced by bone cancer pain, At 0. 5h after administration, the quantification of spontaneous flinches of the two groups ( (7.25 + 1.49 ), (4. 12 + 1.36 ) ) were decreased when compared with control group ( 11.62 + 1.92 ),PWMT((1.28 +0.14)g;(1.75 +0.46)g),PWTL((14.64 +2.12) s; (16.85 + 1.61)s)were increased when compared with control group ( (0.47 + 0. 16) g, ( 11.32 + 1.68 ) s) (P 〈 0.05 =. The effect lasts for at least 4 h and disappears at 8 h. Conclusion CaMK Ⅱ may play an important role in the mechanism of bone cancer pain. Intrathecal KN93 injection can effectively attenuated bone cancer pain.