八肽胆囊收缩素对吗啡成瘾大鼠中枢痛觉的调制  

Modulation of Cholecystokinin on Central Painful Sense of Morphinistic Rats

作　　者：李晋峰[1] 杨春晓[1] 

机构地区：[1]哈尔滨医科大学附属第二医院神经内科,黑龙江哈尔滨150081

出　　处：《现代生物医学进展》2009年第3期422-424,439,共4页Progress in Modern Biomedicine

基　　金：国家自然科学基金资助项目(30240058)

摘　　要：目的:观察八肽胆囊收缩素(CCK-8)对正常及吗啡成瘾大鼠尾核中痛兴奋神经元(PEN)电活动的影响,从而进一步探讨中枢CCK-8和尾核在吗啡成瘾大鼠痛觉调制中的作用。方法:70只Wistar大鼠随机分为2组:正常对照组35只(又分为生理盐水组15只和CCK-8组20只)及吗啡成瘾组35只(又分为生理盐水组15只和CCK-8组20只)大鼠背部皮下注射递增剂量吗啡,依次为5、10、20、40、50、60 mg/kg,3次/d(8:00,12:00,16:00),连续给药6d,建立吗啡成瘾大鼠的模型。正常对照组大鼠背部皮下注射生理盐水,时间、剂量均与吗啡成瘾组相同。第7天8:00观察大鼠的自然戒断症状30 min后开始实验。实验以电脉冲刺激大鼠的坐骨神经作为伤害性痛刺激,用玻璃微电极记录尾核中PEN的放电,观察尾核内注入CCK-8对PEN电活动的影响。结果:实验结果表明:①CCK-8可提高正常大鼠尾核中PEN的兴奋性,即25个PEN平均秒净增值由注射CCK-8前(100%)增加到(224.34±10.81)%,潜伏期缩短到(54.69±5.62)%②CCK-8使吗啡成瘾大鼠尾核中PEN的兴奋性也增高,22个PEN的平均秒净增值比注药前(100%)提高了(118.93±8.50)%,潜伏期缩短了(33.96±7.23)%。结论:CCK-8可使吗啡成瘾与正常大鼠尾核中PEN对电刺激的兴奋性增强,均呈易化疼痛作用,证明中枢CCK-8系统和尾核在吗啡成瘾过程和疼痛的调节中都起到了一定的作用。Objective： To study the effects of cholecystokinin-octopeptide （CCK-8） on the electrical activities of pain excitation neurons （PEN） in the caudate nucleus of normal and morphinistic rats, and to further investigate the modulation of CCK-8 and caudate nucleuson central painful sense of morphinistic rats. Methods： Seventy Wistar rats were randomly divided into normal control group （n =35）, which was subdivided into normal saline group （n 15） and CCK-8 group （n -20）, and morphinism group （n =35）, which was subdivided into normal saline group （n - 15） and CCK-8 group （n = 20）. The morphinism rat models were induced by subcutaneous injection of morphine on the back with gradually increasing dosages of 5, 10, 20, 40, 50 and 60 mg/kg, three times a day at 8：00, 12：00 and 16：00 respectively, for six continuous days. Rats in normal control group were given saline ,the same time and dosage as the morphinism group . The experiment began at 8：00 on the seventh day after to observe the natural withdrawal symptom for 30 minutes. The right sciatic nerve was stimulated by train of electrical impulses as noxious stimuli. The electrical discharges of PEN in the caudate nucleus were recorded with glass microelectrode to observe the influences of microinjection of CCK-8 into caudate nucleus on the electrical activities of PEN. Results： The present study demonstrated that： ① CCK-8 could enhance the excitabilities of PEN in the caudate nucleus of normal rats, i.e. the average net-increased value of 25 PEN was increased from （100%） before microinjection of CCK-8 to （224.34 ± 10.81 ）%, and the latency was shortened from（100%） to （54.69 ± 5.62）%; @ CCK-8 could increase the excitabilities of PEN in the caudate nucleus of the morphinism rats, the average net-increased value of 22 PEN increased （118.93 ± 8.50 ）%, and the latency shortened （33.96 ± 7.23）% in comparison with those before injection CCK-8 （100%）. Conclusions： CCK-8 can enhance the excitabilitie

关 键 词：八肽胆囊收缩素 吗啡成瘾 尾核 痛兴奋神经元 

分 类 号：Q95-33[生物学—动物学] Q954.67