蛋白激酶C抑制剂改善帕金森病大鼠异动症的研究  

Protein kinase C inhibitor improves motor complications in a rat model of Parkinson＇s disease

作　　者：孔敏[1] 宋璐[1] 巴茂文 刘振国[1] 

机构地区：[1]上海交通大学医学院附属新华医院神经内科,200092 [2]山东省烟台市毓磺顶医院神经内科

出　　处：《中华老年医学杂志》2010年第4期314-318,共5页Chinese Journal of Geriatrics

基　　金：上海市科委上海-飞利浦研究与发展基金合作基金（07SP07005）;上海市浦江人才计划[PJ（2007）00346]

摘　　要：目的探讨蛋白激酶C（PKC）抑制剂他莫昔芬对左旋多巴诱发异动症的细胞学与行为学效应。方法将6-羟多巴胺立体定向注射于大鼠前脑内侧束建立帕金森病（PD）动物模型。模型成功的PD大鼠接受每天2次左旋多巴（50mg／kg左旋多巴＋12．5mg／kg苄丝肼）腹腔注射，持续22d。在第23天左旋多巴注射前，2组PD大鼠给予他莫昔芬或溶剂处理。评估旋转反应时间及剂峰旋转次数，采用蛋白印迹法检测纹状体区N-甲基-D-天冬氨酸受体NR1亚单位（NR1）和890、896位丝氨酸位点磷酸化的NR1（NR1S890、NR1S896）表达情况。结果PKC抑制剂他莫昔芬减轻少了左旋多巴诱导的PD大鼠剂峰旋转次数[（121.0±7．6）次与（161．5±22．1）次，t=2．6。P〈0．053；此外。他莫昔芬能调节与异动症密切相关的NR1的亚细胞分布，使纹状体部位NR1在膜蛋白中的表达量减少至（82．4±5．1）％，与左旋多巴＋溶剂组[（103．0±3．5）％]比较差异有统计学意义（t=6．7，P〈0．05），同时使NR1S890、NR1S896的磷酸化水平明显降低，其表达量分别为（77．2±4．2）％与（98．4±6．4）％（t=5．9、3．6，均P〈0．05）。结论长期左旋多巴作用激活了纹状体棘状神经元内丝氨酸激酶PKC，并导致谷氨酸受体磷酸化，从而出现了异动症；抑制丝氨酸激酶（如PKC）活性的药物可能是治疗及预防帕金森病异动症的一种新的治疗方式。Objective To investigate the cytological and behavioral effects of protein kinase C （PKC） inhibitor tamoxifen on levodopa-induced motor complications of a rat model. Methods The hemi parkinsonian rat model was produced by stereotaxically injecting 6-hydroxydopamine （6-OHDA） into right medial forebrain bundle （MFB）. Two sets of experiments were performed. First, rats were intraperitoneally treated with 50 mg/kg levodopa plus 12.5 mg/kg benserazide, twice daily for 22 days. On day 23, the rats received either tamoxifen or vehicle before levodopa administration. Rotational duration and peak rotation were estimated. After being sacrificed, subcellular distribution and phosphorylation （S890 and S896） of N-methyl -D-aspartate receptor subunit 1 （NR1） were observed by Western blot. Results Our study showed that tamoxifen reduced peak rotation [（121.0±7.6） times vs. （161.5 ± 22. 1） times, t=2.6, P〈0.05]. Moreover, tamoxifen could regulate subeellular distribution of NR1 which was closely associated with levodopa induced motor complications, reduce the expression of NR1 in the membrane protein as compared with levodopa＋ vehicle group [（82.4% ± 5.1%0） vs. （103.0%± 3.5%）, t= 6.7, P〈0.05], and reduce the phosphorylation of NRLS890 （77.2%± 4.2%） and NR1S896 （98.4% ± 6.4%）, respectively （t = 5.9,3.6,both P〈 0.05）. Conclusions These results indicate that chronic levodopa treatment activates serine kinase and leads to phosphorylation of glutamate receptors, and thus contributes to development of motor complications. Pharmaceuticals which inhibit serine kinase, such as PKC, may be useful in the treatment and prevention of motor complications in parkinsonian patients.

关 键 词：帕金森病 蛋白激酶抑制剂 左旋多巴 

分 类 号：R742.5[医药卫生—神经病学与精神病学]