CNQX对电刺激隐神经诱发大鼠扣带回前部神经元c-Fos基因表达的影响

目的阐明伤害性电刺激隐神经(saphenous nerve,SN)能否引起扣带回前部(anterior cingulategyrus,ACG)神经元c-Fos基因表达及其发生机制。方法用免疫组化方法研究伤害性电刺激SN后不同时间,ACG神经元c-Fos基因表达的变化,以及尾静脉注射α-氨基3-羟基5-甲基4-异恶唑丙酸/海人藻氨酸(α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid/kainate,AMPA/kainate)受体拮抗剂受体是谷氨酸受体之一,6-氰基-7-硝基喹喔啉-2,3-二酮(6-cyano-7-nitroquinoxaline-2,3-dike-tone,CNQX)对该变化的影响。结果伤害性电刺激SN后30 min ACG神经元Fos蛋白表达明显增加,60 min增加最明显,120 min后开始消退;并且尾静脉注射CNQX拮抗了伤害性电刺激SN引起的ACG神经元Fos蛋白表达的显著增加。结论伤害性电刺激SN能够引起ACG神经元Fos蛋白表达的显著增加,这种表达呈时间依赖性,提示ACG存有SN代表区,能够感受SN传入的伤害性信息;CNQX拮抗了伤害性电刺激SN引起的ACG神经元Fos蛋白表达的显著增加,提示AMPA/kainate受体参与此过程。

Effect of CNQX on c-Fos gene expression of neurons in anterior cingulate gyrus of rats induced by electrically stimulating saphenous nerve

Objective To elucidate whether noxious electrical stimulating saphenous nerve(SN) can cause c-Fos gene expression in anterior cingulate gyrus(ACG) neuron and its mechanism. Methods Immunohistochemistry method was used to investigate effect of different time after electrically stimulating SN on c-Fos gene expression in ACG neurons of rats, and the influence of vena caudalis injection of AMPA/kainate（α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid/kainate） receptor antagonist CNQX(6-cyano-7-nitroquinoxaline-2,3-diketone) to the c-Fos gene expression in ACG neurons of rats induced by electrically stimulating SN. Results Fos protein expression in ACG neurons significantly increased at 30 min after electric stimulation SN, and reached its peak at 60 min after stimulating SN, and started to decrease at 120 min after stimulating SN. In addition, vena caudalis injection of CNQX antagonized the Fos protein expression in ACG neurons caused by noxious electric stimulation on SN. Conclusion Noxious electric stimulating SN could significantly increase the expression of Fos protein in ACG neurons, which was time-dependent, and antagonized by CNQX. The study suggested that ACG is one of the representative areas of SN afferent pathway, and ACG can receive the nociceptive afferent information by SN, and AMPA/kainate receptors take part in the course of increase in Fos protein expression in ACG induced by noxious electric stimulation on SN.