尾核中NMDA和非NMDA受体参与皮层SmI对丘脑束旁核伤害性反应的下行性调节

Participation of NMDA and Non-NMDA Receptors in Caudate Nucleus in SmI Emanating Descending Modulation of Nociceptive Responses in Parafascicular Nucleus

本文探讨尾核中ＮＭＤＡ和非ＮＭＤＡ受体是否参与皮层体感运动Ｉ区（ＳｍＩ）对丘脑束旁核（Ｐｆ）伤害性反应和针刺镇痛的下行性调节。结果发现，双侧尾核头部分别微量注射ＮＭＤＡ受体的拮抗剂Ｄ－ＡＰ５（ｎ＝１１）和非ＮＭＤＡ受体拮抗剂ＤＮＱＸ（ｎ＝９）后谷氨酸兴奋皮层ＳｍＩ对Ｐｆ神经元伤害性反应的抑制效应均被明显减弱，与盐水对照组（ｎ＝１３）的抑制效应相比，均有显著差别（ ＡＮＯＶＡ， Ｐ＜ ０． ０５）。尾核内微量注射 ＤＮＱＸ后，电针（ ｎ＝１１）抑制 Ｐｆ神经元伤害性反应的效应 显著减弱，与盐水对照组相比，差别显著（ＡＮＯＶＡ，Ｐ＜０．０５）。提示尾核中ＮＭＤＡ和非ＮＭＤＡ 受体均参与兴奋皮层 ＳｍＩ对 Ｐｆ神经元伤害性反应的下行调节，而非 ＮＭＤＡ受体还参与电针对 Ｐｆ 神经元伤害性反应的抑制作用。

The present study aimed to investigate whether NMDA and non-NMDA receptors in the caudate nucleus (Cd) were involved in SmI originating descending modulation on neurons in parafascicular nucleus (Pf) in acupuncture analgesia. It was found that after bilateral microinjection of D-AP5 and DNQX, the antagonist of NMDA and non-NMDA receptors respectively, into the head of Cd the inhibitory effect of conical excitation induced by glutamate application at SmI was obviously diminished, compared with that in the saline control group (ANOVA, P < 0. 05 ). In addition, the inhibitory effect of electro-acupuncture (EA) on nociceptive responses of neurons in Pf was also significantly attenuated by microinjection of DNQX, but not by that of D-APS. The attenuation was also significant statistically (ANOVA, P < 0. 05 ). It is indicated that both NMDA and non-NMDA receptors in Cd are involved in SmI originating descending modulation on nociceptive responses of neurons in Pf. Besides, non-NMDA receptors also participate in EA-induced inhibition on nociceptive responses of neurons in Pf.