刺激下肢胫后神经引起的体感诱发电位痛成分-P250-N350

The Components of Somatosensory Evoked Potentials P250-N350 Induced by Nervi Tibialis Posterior Stimulation

实验用压迫阻断血循的方法，分折刺激下肢胫后神经引起的体感诱发电位（SEPs）痛成份。结果表明：在强痛刺激下，于250毫秒处出现一正向波（平均潜伏期244．2±10．lms），随后350毫秒处有一负向波（344．2±14.7ms），此复合电位称为P250－N350。当阻断血流至触觉消失后，SEPs的其它成份基本消失，而痛觉存在即被保留的复合电位P250－N350还存在，但潜伏期已有所延迟（270.8±15．1ms）。血流继续阻断，至痛觉也消失时，此成份也消失。当血行恢复后，记录SEPs与阻断前相同，故该成份可以认为是下肢胫后神经SEPs的痛成份。

The pain components of somatosensory evoked potentials (SEPs)induced by nervi tibialis Posterior stimulation were studied by blocking bloodstream of leg in 10 normal adults. The SEPs following the painful stimuli (0. 1 msec square wave pulse)of the right ankle were recorded from the parietal median (C'Z)and the reference electrode at earlob. The pressure of 80 mmHg avove the arterial pressure was given to the right calf by sphygmomanometer. The result showed that the P250-N350 components (latency 244. 2±10. 1 msec and 344. 2±14.9 msec)of the SEPs persisted and the others disappeared when tactile sensation disappeared but pain existed. It suggested the P250-N350 were the pain potentials of nervi tibialis posterior SEPs.