我们以往工作证明

猫的十字沟前皮层参与对丘脑中央中核(CM)伤害性反应的下行性调节。本文比较了用利多卡因局部改变十字沟前皮层和 SI 区机能状态前后电针对 CM 神经元伤害性反应的影响

以探讨十字沟前皮层和 SI 区是否参与对 CM 核电针效应的下行性调节。实验用猫

硫贲妥钠麻醉下开颅

暴露右侧十字沟周围皮层

于同侧 CM 核上方颅骨钻孔。分离左侧(?)浅神经

以便施以伤害Extracellular recordings were made to investigate the influences of topical application of lidocaine at the preeruciate cortex and the primary somatosensory area(SI)

respectively

on the inhibitory effect of electroacupuncture(EA)at“Huantiao”and“Zusanli”points on nociceptive responses of neurons in the nucleus centrum medianum (CM) in the cat.It was found that topical administration of lidocaine at either the precruciate cortex or the SI area suppressed the inhibitory effect of EA on nociceptive responses of CM neurons

whereas in the control group

administered with normal saline (N.S.) at either of the two cortical areas

EA produced remarkable inhibitory effect on the nociceptive responses.The difference was statistically significant between the two groups. Similarly

when the comparison of the EA effets induced on the background of lidocaine and N.S.application successively at either of the two cortical areas was made in same individual CM neurons

lidocaine application exhibited obvious suppresive action on the analgesic effect of EA.The suppression was stronger and more prolonged when lidocaine was applied at the precruciate cortex than at the SI area.The roles of the precruciate cortex and the SI area in descending regulation of EA effects in CM neurons were discussed.