摘要
目的研究谷氨酸受体拮抗剂6-氰基-7-硝基喹喔啉-2,3-二酮(CNQX)对截断尾末端后小鼠痛反应变化的影响,为深入研究截肢后中枢的可塑性变化及幻肢痛产生机制提供理论依据。方法采用热板法分别于截断小鼠尾末端2.5cm前及截断后0.5h、1h、2h、3h、24h、168h(1周)测量断尾小鼠的痛阈,并观察尾静脉注射CNQX对断尾后小鼠痛阈变化的影响。结果与对照组及断尾前比较,小鼠断尾后0.5h、1h,痛阈无明显变化;小鼠断尾后2h,痛阈显著升高(P<0.01);断尾后3h,升高的痛阈开始恢复(P<0.05);断尾后24h、168h,小鼠痛阈基本恢复正常。CNQX拮抗了断尾诱发小鼠痛阈升高的反应。结论断尾后2～3h,小鼠后肢皮肤对温热性伤害刺激产生痛反应的阈值提高;谷氨酸AMPA/Kainate受体参与该痛阈提高的过程。
Objective To investigate the effect of glutamic acid receptor antagonist CNQX on the change of pain responses of mice after amputation of extremity of the tail.Methods The distal 2.5 cm length of the mouse tail was removed as an experiment model of amputation.Hot plate experiment was used at 0.5 h,1 h,2 h,3 h,24 h,168 h after the amputation,respectively.The latencies of the mice′s licking their hindpaws on the hot plate（55±1 ℃） were recorded and used as an index of pain threshold by hot plate method.Mice were removed from the chamber if they did not respond within 60 s,and the response latency was recorded as 60 s.The change of pain response was observed after CNQX was injected by the caudalis vein.Results There was no significant change in pain threshold between control or preamputating and amputating groups at 0.5 h or 1 h after the amputation （P 〉 0.05）.Pain threshold of 2 h or 3 h groups after the amputation was significantly higher than that of their control groups or before the amputation （P 〈 0.01）.There was no significant change in pain threshold between 24 h or 168 h groups after the amputation,compared with that of their control groups or before the amputation（P 〉 0.05）.The intravenous injection of glutamic acid receptor antagonist CNQX antagonized the increase in mice′s pain threshold at 2 h after the amputation.Conclusion Threshold of pain responses of the mice to the hot plate is significantly increased at 2 to 3 h after the amputation of extremity of the tail in mice.The AMPA/Kainate receptor is involved in the increase in pain threshold induced by the amputation.
出处
《中国医科大学学报》
CAS
CSCD
北大核心
2011年第1期48-49,52,共3页
Journal of China Medical University
