新生期母婴分离对幼鼠内脏痛敏感性及脊髓Fos蛋白表达的影响  

Effect of neonatal maternal separation on visceral hyperalgesia in the developing rats and role of fos abnormal expression in spinal cord

作　　者：林滨榕[1] 吴斌[1] 卓玲[1] 陈兢芳[1] 杨燕珍[1] 张睿[1] 

机构地区：[1]福建医科大学附属第一医院儿科,福州350005

出　　处：《中国新生儿科杂志》2010年第2期89-93,共5页Chinese Journal of Neonatology

基　　金：福建省卫生厅青年科研课题(2008-2-22);福建省教育厅科技项目(JB08094);福建医科大学第一临床医学院学科带头人培养对象专项基金(JXK200716)

摘　　要：目的探讨新生期母婴分离(MS)对幼鼠内脏痛觉敏感性及脊髓背角Fos蛋白表达的影响。方法按析因设计,32只SD新生大鼠分成4组,每组8只,A1B1组为MS组并在6周龄时接受结直肠扩张刺激(CRD),A1B2组为MS组,6周龄未给予CRD,A2B1组未MS在6周龄接受CRD,A2B2组未MS,且6周龄未给予CRD。A1B1组、A2B1组6周龄时进行CRD下腹壁撤退反射(AWR)评分和痛阈测定;A1B1组、A2B1组幼鼠在CRD刺激后2h和A1B2组、A2B2组幼鼠一起处死,留取L6至S2脊髓,应用免疫组织化学染色及计算机图像分析系统进行脊髓Fos阳性(FLI)细胞数半定量分析。结果CRD压力为20、40、60、80mmHg时,A1B1组AWR评分分别为(2.2±0.7)、(3.2±0.6)、(3.8±0.4)、(4.0±0.0)分,A2B1组分别为(1.0±0.8)、(2.5±0.3)、(3.3±0.3)、(3.9±0.2)分;CRD为20、40、60mmHg时,两组差异有统计学意义。A1B1组和A2B1组痛阈值分别为(17.9±8.9)mmHg、(33.5±1.9)mmHg,差异有统计学意义(P=0.000)。A1B1组、A2B1组、A1B2组和A2B2组幼鼠腰骶段脊髓背角FLI细胞数分别为(18.3±3.4)、(11.4±1.1)、(14.3±1.3)和(9.1±0.4)个,新生期MS和幼鼠6周龄时CRD均可使幼鼠腰骶段脊髓背角FLI细胞数显著升高(P均<0.01)。结论新生期MS可导致幼鼠内脏痛觉敏感性增高和痛阈下降,脊髓初级中枢对内脏痛觉敏感化,接受伤害性CRD后引起脊髓神经元Fos蛋白高表达,出现慢性内脏痛觉高敏感性。Objective To explore the effect of maternal separation （MS） stimulation in neonatal period on visceral sensitivity of pain in developing rats. Observeing the Fos expression at dorsal horn of lumborsacral spinal cord in rats to investigate the mechanism of highly visceral pain sensitivity. Methods According to the factorial design,32 SD rats were divided into four groups of 8 each. Group A1B1 was experimental group and subjected to colorectal distention （CRD） at 6-week age,yet group A1B2 were not imposed on CRD as the experimental group. Group A2B1 was subjected to colorectal CRD at 6-week age while group A2B2 without treatment both as the control groups. Rats in the MS group were separated from the dam for 3h/d （8：00-11：00 am） on postnatal days 2-14 for 13 consecutive days,rats in control group rats were not treated and remained in the home cage with the dam. When 6 weeks old,the rats of group A1B1 and A2B1 were evaluated the pain sensibility of intestinal tract under colorectal distension irritation by the method of observing the score of abdominal withdrawal reflex （AWR） and visceral pain threshold subjected to different pressures of colorectal distension irritation （CRD） to evaluate visceral algesthesia in rats. The rats were sampled the spinal cord from L6 to S2 after the group A1B1 and A2B1 were subjected to colorectal CRD for 2 hours while the group A1B2 and A1B2 not subjected to colorectal CRD. The semiquantity analysis of the cell number of Fos-Like Immunoreactivity（FLI） in spinal cord were made through immuno-hisrochemical coloration and computer image analyzing system. Results While CRD pressure were 20 mmHg,40 mmHg,60 mmHg,80 mmHg,the score of AWR were 2.2±0.7,3.2± 0.6,3.8±0.4,4.0±0.0 in group A1B1,and 1.0±0.8,2.5±0.3,3.3±0.3,3.9±0.2 in group A2B1. When the CRD pressure were 20 mmHg,40 mmHg,60 mmHg,the AWR score was higher in the A1B1 group than the group A2B1 signigficantly. But when pressure reached 80 mmHg,there was no significant differenc

关 键 词：痛觉过敏 原癌基因蛋白质C-FOS 母婴分离 大鼠 

分 类 号：R722.1[医药卫生—儿科]