皮层体感Ⅰ区神经元对伤害性电刺激腓总神经的反应——细胞内电位研究

RESPONSES OF NEURONS IN THE SOMATOSENSORY AREA I TO NOXIOUS ELECTRIC STIMULATION OF NERVUS PERONEUS COMMUNIS The Study of Intracellular Potentials

腓总神经是小腿和足背的主要感觉神经,以伤害性强电刺激腓总神经可以导致动物的痛反应,如反射性下颌运动及血管紧张性收缩等,并可诱发脑内核团痛放电;

Noxious electric stimulation of ncrvus pcroneus communis (PN) results in pain. It hasn't been reported that the neurons in somatosensory area I(SI) may respond to the noxious stimulation. In this paper, using intracellular microelectrode technique, we have studied the responses of neurons in SI to noxious electric stimulating PN. 33 neurons were recorded in 18 cats. 16 neurons were related with the noxious stimulation. The responses of these neurons to noxious stimulation were mainly inhibitory postsynaptic potentials (IPSP). Some neurons responded with two IPSPs. A few neurons responded with EPSP(Excitatory postsynaptic potential)-IPSPs. The latencies of the first IPSPs were short(8.25±5.90ms) and showed that the first IPSPs might be induced by the input of Aβ fiber. The latencies of the second IPSPs (In the neurons with two IPSPs) were long (60.33±6.62ms) and showed lhat the second IPSPs might be induced by the input of A6 fiber. Above results show That: 1) SI neurons can respond to the noxious electric stimulation of PN.2) The responses of SI neurons to the noxious stimulation were mainly IPSPs.3) The second IPSPs might be related with pain.