MK-801对断尾小鼠痛阈及血清褪黑素含量影响  

Effect of MK-801 on pain threshold and serum melatonin content in mice with amputation of tail extremity

作　　者：李玉芳[1] 吴敏范[1] 代秋竹[1] 陈魁敏[2] 商丽宏[2] 杨宇[1] 

机构地区：[1]沈阳医学院生理学教研室,辽宁沈阳110034 [2]沈阳医学院机能实验中心

出　　处：《中国公共卫生》2011年第8期1017-1018,共2页Chinese Journal of Public Health

摘　　要：目的观察谷氨酸N-甲基-D-天冬氨酸(NMDA)受体拮抗剂MK-801对尾末端截断后小鼠痛阈及血清褪黑素含量影响,为进一步研究截肢后中枢可塑性变化提供实验依据。方法分别在小鼠尾末端2.5 cm截断后0.5、1、2、3 h、1 d、1周用热板法测定断尾小鼠痛阈,用ELISA法测定小鼠血清褪黑素含量,以及观察静脉注射MK-801对断尾后小鼠痛阈及血清褪黑素含量影响。结果对照组小鼠痛阈为(18.24±5.06)s,断尾前小鼠痛阈为(18.40±5.42)s,断尾后0.5、1 h,小鼠痛阈无明显变化;断尾后2 h,小鼠痛阈[(23.78±3.57)s]明显升高(P<0.01);断尾后1 d小鼠痛阈基本恢复正常;MK-801拮抗了断尾诱发小鼠痛阈升高的反应,小鼠痛阈为(15.41±7.00)s,对照组小鼠血清褪黑素含量为(155.750±61.577)pg/mL,断尾后2 h,小鼠血清褪黑素含量降低为(82.207±19.871)pg/mL,MK-801干预后小鼠血清褪黑素含量为(131.783±36.637)pg/mL。结论 NMDA受体参与了断尾诱发小鼠痛阈提高及血清褪黑素含量降低过程。Objective To study the effect of N-methyl-d-aspartate（NMDA） receptor antagonist-MK-801 on pain threshold and serum melatonin content of the mice after amputation of tail extremity and to provide experimental data for the study on plastic changes in central nervous system after amputation.Methods The mice with amputated distal tail of 2.5cm were served as the experiment model of amputation.The latencies of the mice licking their hindpaws on the hot plate（55±1 ℃） were recorded at 0.5 hr,1 hr,2 hr,3 hr,1 day,and 1 week after the amputation and were used as indexes of pain threshold.If the mice did not respond within 60 seconds,the mice were removed from the hot plate,and the latency was recorded as 60 s.MK-801 was injected via caudalis vein.The blood of the mice was obtained by cutting the heads after the hot plate experiment.The serum melatonin contents were measured with enzyme-linked immunoabsorbent assay.Results Compared with that of control group（18.24±5.06 s,n=15） and before the amputation（18.40±5.42 s,n=15）,the pain threshold was not obviously changed at 0.5 hr and 1 hr after the amputation（P0.05）,but was significantly increased at 2 hr（23.78±3.57,n=15,P0.01）,3 hr（22.42±6.71 s,n=15,P0.05）,and 1 day and 1 week after the amputation（P0.05）.Compared with that of the control group（155.750±61.577 pg/ml,n=10）,the serum melatonin content 2 hr after the amputation was significantly decreased（82.207±19.871 pg/ml,n=9,P0.05）.The intravenous injection of MK-801 antagonized both the increase of pain threshold（15.41±7.00 s,n=9） and the decrease of serum melatonin content（131.783±36.637 pg/ml,n=7） 2 hr after the amputation.Conclusion The results indicate that NMDA receptor is involved in the processes of the increase in pain threshold and the decrease in serum melatonin content induced by amputation in mice.

关 键 词：截肢 幻肢痛 谷氨酸N-甲基-D-天冬氨酸(NMDA)受体 褪黑素 小鼠 

分 类 号：R338.3[医药卫生—人体生理学] Q432[医药卫生—基础医学]