谷氨酸及NMDA受体拮抗剂MK-801对大鼠伏核痛兴奋神经元电活动的影响  

Influence of glutamate and NMDA-receptor antagonist MK-801 on the electric activities of pain-excitation neurons in the nucleus accumbens of rats

作　　者：张秀娟[1] 徐满英[2] 吕宁[2] 

机构地区：[1]广东医学院生理教研室,湛江524023 [2]哈尔滨医科大学生理教研室,哈尔滨150086

出　　处：《生理学报》2005年第1期66-70,共5页Acta Physiologica Sinica

基　　金：This work was supported by the National Natural Science Foundation of China ( No.30240058)

摘　　要：本文研究了谷氨酸(glutamicacid,Glu)及其NMDA受体拮抗剂5-甲基二氢丙环庚烯亚胺马来酸(MK-801)对大鼠伏核(nucleusaccumbens,NAc)痛兴奋神经元(pain-excitationneurons,PEN)痛诱发反应的影响。电刺激坐骨神经作为伤害性刺激,用玻璃微电极记录NAc的PEN放电,观察脑室内注射Glu和NAc内注射MK-801对大鼠NAc中PEN伤害性诱发活动的影响。结果显示,伤害性刺激可使NAc的PEN电活动增强;脑室内注射Glu(10nmol/10μ1)可使NAc的PEN伤害性诱发放电频率增加;NAc内注射MK-801(1.0nmol/0.5μ1)可阻断这种作用;MK-801本身也可部分抑制PEN伤害性诱发反应。上述结果表明,Glu对PEN伤害性反应的易化作用是通过NMDA受体介导的;Glu和NMDA受体参与NAc伤害性信息传递的调制。The experiment explored the influence of glutamic acid (Glu) and the NMDA-receptor antagonist dizocilpine maleate (MK-801) on the pain-evoked responses of pain-excitation neurons (PEN) in the nucleus accumbens (NAc) of rats. The trains of electric impulses applied to the sciatic nerve were used as noxious stimulation. The discharges of PEN in NAc were recorded by glass microelectrode. We observed the influence of intracerebroventricular (icv) injection of Glu and microinjection of MK-801 into the NAc on the noxious stimulation-evoked activities of PEN in NAc. The results showed that the noxious stimulation potentiated the electric activities of PEN in NAc. Intracerebroventricular injection of Glu (10 nmol/10 μl) increased the frequency of the discharge of PEN evoked by the noxious stimulation in NAc, the Glu-induced response was blocked by the injection of MK-801 (1.0 nmol/0.5 μl) into NAc. MK-801 partly inhibited the response of PEN upon the noxious stimulation. It is therefore suggested that the facilitatory effect of Glu on PEN response in NAc to the noxious stimulation is mediated by NMDA receptors, and that Glu and NMDA receptors are involved in the modulation of nociceptive information transmission in the NAc.

关 键 词：谷氨酸 MK-801 伏核 痛兴奋神经元 电活动 

分 类 号：Q426[生物学—神经生物学] R338[生物学—生理学]