【摘要】 <正> 一些实验研究证明,刺激牙髓只产生痛觉,而它所诱发的张颌反射(Jaw Open-ing Reflex)与痛觉有关。电针对这种反射有明确的抑制作用,并以此来客观评价针刺镇痛反应。1978年以来,日本户田等对电针抑制牙髓诱发性张颌反射的外周作用机制曾作过详细的研究,而对其中枢的作用环节,目前尚不清楚。本实验主要研究中枢神经系统在电针抑制牙髓诱发性张颌反射中的作用。实验分为两部分,一是观察电针对牙髓诱发性张颌反射的影响;二是观察去掉不同脑区后电针镇痛效应的影响。更多还原

【Abstract】 Jaw opening reflex (JOR) induced by tooth pulp stimulation and re- corded electromyographically from the ipsilateral digastric muscle was studied on 61 rabbits under light anesthesia. Electro-stimulation of ipsila- teral superficial radial nerve initiated an immediate and marked suppres- sion of this reflex which showed two phases: 1. Early phase, the JOR was suppressed as soon as the electro-stimula- tion was started which attained its maximal effect within half a minute and persisted for 2.5-5 minutes. This effect could not be reversed by na- loxone, but was abolished after decerebration rostral to superior colliculi of midbrain. 2. Late phase, prolonged moderate suppression of JOR was noticed under continuous electrostimulation which persisted even after cessation of stimulation for 5 minutes. This effect could be partially reversed by naloxone and was abolished after ablation of diencephalon. It is thus concluded that the early phase of the suppressive effect on tooth pulp induced JOR by electroacupuncture involves the central mechanism located rostral to the superior colliculi of midbrain, while its late phase is mediated through diencephalon in which the endogenous morphine like sub- stance might be involved.更多还原