家兔伏核-杏仁核神经通路在吗啡镇痛中的作用  

THE NEURAL PATHWAY FROM NUCLEUS ACCUMBENS TO AMYGDALA IN MORPHINE ANALGESIA OF THE RABBIT

作　　者：于龙川[1] 韩济生[1] 

机构地区：[1]北京医科大学生理教研室

出　　处：《生理学报》1990年第3期277-283,共7页Acta Physiologica Sinica

摘　　要：用辐射热照射家兔鼻嘴侧部皮肤,测量其躲避反应潜伏期作为痛反应阈,简称痛阈。通过预先埋植的慢性套管向伏核或杏仁核内进行注射,结果表明:(1)在家兔的伏核内微量注射吗啡可产生镇痛作用,该作用可被杏仁核内注射纳洛酮所削弱,并有量效依从关系;在杏仁核内注射甲啡肽抗血清(ME AS)或β-內啡肽抗血清(β-EP AS)亦可削弱上述镇痛作用;(2)在杏仁核内微量注射吗啡可产生镇痛作用,此作用不能被伏核内注射纳洛酮所阻断;(3)在伏核内注射吗啡所产生的镇痛作用可被同一部位注射γ-氨基丁酸(GAEA)受体阻断剂氯甲基荷包牡丹碱所增强,被 GABA 受体激动剂异鹅羔胺所削弱。上述结果提示:在家兔脑内从伏核到杏仁核可能存在一条与镇痛有关的神经通路,伏核内的阿片样物质及杏仁核内的甲啡肽,β-内啡肽可能参与镇痛信息的传递,而伏核内的 GABA 可能有对抗吗啡镇痛的作用。The purpose of this study was to explore possible neural connections betweenthe nucleus accumbens and amygdala involved in analgesia.The latency ofthe escape response elicited by radiant heat applied on snout of the rabbit wastaken as an index for nociception.It was found that:(1)the analgesic effectelicited by intra-accumbens injection of morphine was attenuated dose-depend-ently by intra-amygdala administration of opioid antagnist naloxone,or antiseraagainst met-enkephalin(ME)or β-endorphin(β-EP),suggesting the involve-ment of ME and β-EP in the accumbens-amygdala connection;(2)the anal-gesia produced by intra-amygdaloid injection of morphine was not affected bynaloxone administered to nucleus accumbens,suggesting a one-way connec-tion between the two nuclei;(3)the analgesia of intra-accumbens injection ofmorphine was significantly attenuated by muscimol,the GABA receptor agonist,and enhanced by bicuculline methochloride,the GABA receptor antagonist in-jected into the same site where morphine was administered.The results suggestthat the analgesic effect of morphine administered to the nucleus accumbens ismediated by the suppression of the GABAergic inhibitory neurons located withinthe nucleus.

关 键 词：伏核 杏仁核 吗啡镇痛 纳洛酮 阿片肽 Γ-氨基丁酸 

分 类 号：R338.26[医药卫生—人体生理学]