P2Y12受体抑制剂对骨癌痛大鼠痛阈及脊髓p38丝裂原活化蛋白激酶表达的影响  

Influence of P2Y12 receptor inhibitor on pain threshold and spinal p38MAPK in rat bone cancer pain model

作　　者：朱艳丽[1] 刘明娟[1] 倪华栋[1] 姚明[1] 黄冰[2] 周煦燕[2] 孙建良[2] 连庆泉[1] 

机构地区：[1]温州医学院麻醉系,浙江省325027 [2]嘉兴学院附属第一医院麻醉与疼痛科

出　　处：《中华医学杂志》2012年第39期2785-2788,共4页National Medical Journal of China

基　　金：中西医结合疼痛医学重点学科建设（2012-XK-A31）;浙江省卫生高层次创新人才培养工程项目（2012-22）

摘　　要：目的研究脊髓P2Y12受体在大鼠骨癌痛中的作用及其对p38丝裂原活化蛋白激酶（p38MAPK）表达的影响。方法雌性SD大鼠40只，用随机数字表法分为5组（n=8）：正常组（N）、假手术组（S）、DMSO溶剂骨癌痛组（DA）、骨癌痛组（A）、骨癌痛镇痛组（MA）。大鼠左胫骨上段注入经腹水培养的Walker256癌细胞建立骨癌痛模型。建模后第9—12天分别行鞘内注药，S组、A组注射0．9％生理盐水，DA组注射5％二甲基亚砜（DMSO）溶剂，MA组注射MRS2395（400pmol／μl，溶于5％DMSO溶液），容量各15μl。注药前后测试大鼠左后足机械痛阈值，术后第12天测完痛阈后取L4～6脊髓，采用免疫组化及免疫荧光法测定脊髓背角磷酸化p38MAPK（p—p38MAPK）表达水平。结果建模后第9天，与N组（36．1±4．0）g、S组（38．9±5．2）g比较，MA组机械性痛阈值下降为（19．8±5．0）g（P〈0．01），第12天p-p38MAPK表达增加（P〈0．01）。与DA组（17．7±3．0）g、A组（19．1±2．5）g比较，MA组鞘内给药后大鼠机械痛阈值增高，峰值为（26．5±4．7）g（P〈0．05）；与DA组（细胞数：43．4±3．8、IOD值：569±27）、A组（细胞数：45．0±2．6、IOD值：594±22）比较，MA组（细胞数：20．9±2．2、IOD值：246±25）第12天脊髓P—p38MAPK表达减少（P〈0．01）；但与N组、S组比较，MA组机械痛阈值仍低于正常（P〈0．01），脊髓p-p38MAPK蛋白表达高于N组（细胞数：9．9±2．4、IOD值：82±28）、S组（细胞数：10．9±2．2、IOD值：109±25）（P〈0．01）。免疫荧光双标显示脊髓背角p-p38MAPK与小胶质细胞共表达。结论鞘内注射P2Y12受体抑制剂MRS2395可能通过抑制脊髓背角的p38MAPK磷酸化程度部分减轻大鼠骨癌疼痛。Objective To investigate the role of P2Y12 receptor in rat bone cancer pain model and its influence on p38MAPK （Mitogen-activated protein kinase）. Method A total of forty female SD rats, weighting 200 - 250 g, were randomly divided into 5 groups （ n = 8） ： normal group （ group N）, sham group （ group S）, vehicle group （group DA）, cancer group （group A）, and analgesia group （group MA）. Rats in group N were untreated, rats in group S were injected with Hank＇s solution 10 μl into the left tibal metaphysis; rats in group DA, group A and group MA were injected with Walker256 cancer cells （10 μl, 2 × 10^7 cells/ml） into the left tibal metaphysic to establish the model of bone cancer pain. Catheterization was simultaneously made in four groups between L3 and L4 vertebra except group N. Saline （0. 9%, 15 μl） was injected in group S and group A, DMSO （5%, 15μl） was injected in group DA, and MRS2395 （400 pmol/μl, 15 μl） was injected in group MA on day 9 to 12 post-inoculation. Mechanical withdrawal thresholds were measured on left hind paw before and every 10 min after intrathecal injection. Rats were euthanized after measuring mechanical withdrawal threshold at day 12 post-inoculation. L4 -6 sections of spinal cord were collected to determine the expression of p-p38MAPK by immunohistochemistry and immunofluorescent. Result Compared to that in group N （36. 1 g ±4. 0 g） and group S （38. 9 g±5.2 g）, mechanical withdrawal thresholds in group MA （ 19. 8 g ±5.0 g） were decreased on day 9 post-inoculation （P 〈0. 01 ）, and the expression of p-p38MAPK in spinal cord was increased on day 12 （P 〈 0. 01 ）. Compared to that in group DA （17.7 g ±3.0 g） and group A （ 19. 1 g ±2. 5 g）, mechanical withdrawal threshold in group MA was obviously increased after intrathecal injection, peaked at （26. 5 g ±4. 7 g） （ P 〈 0. 05 ） ; compared with group DA （ number 43.4 ±3.8, IOD 569 ±27 ） and group A （ number 45.0 ±2. 6, IOD 594 ±22 ）

关 键 词：骨癌痛 P2Y12受体 P38丝裂原活化蛋白激酶 脊髓 

分 类 号：R738[医药卫生—肿瘤]