Di Lazzaro V, Restuccia D, Nardone R, Oliviero A, Profice P, Insola A, Tonali P, Rothwell J C
Instituto di Neurologia, Università Cattolica, Rome, Italy.
J Neurol Neurosurg Psychiatry. 1996 Dec;61(6):641-4. doi: 10.1136/jnnp.61.6.641.
Paired stimulation of the common peroneal and posterior tibial nerve was used to study the recovery cycle of lumbosacral somatosensory evoked potentials in 10 control subjects and in one patient with rhythmic segmental myoclonus of the leg involving the L2-L4 myotomes. In normal subjects the peripheral nerve volley in the cauda equina had recovered at an interstimulus interval of 3 ms whereas the postsynaptic dorsal horn potential was reduced to about 60% of its control size. Similar results were found in the patient after posterior tibial nerve but not common peroneal nerve stimulation. The second, which evokes afferent input to the affected lumbar segments, produced facilitation of the postsynaptic response at 3 ms. This finding suggests that the physiological suppression of dorsal horn interneurons which usually takes place after paired stimulation fails to occur in segmental myoclonus. This may indicate that dorsal horn interneurons are abnormally hyperactive and are involved in the pathophysiology of spinal myoclonus.
对10名对照受试者和1例患有累及L2-L4肌节的腿部节律性节段性肌阵挛的患者，采用腓总神经和胫后神经配对刺激来研究腰骶部体感诱发电位的恢复周期。在正常受试者中，马尾神经中的外周神经冲动在刺激间隔为3毫秒时已恢复，而突触后背角电位降至其对照大小的约60%。在胫后神经而非腓总神经刺激后，该患者也发现了类似结果。第二次刺激会引起受影响腰段的传入输入，在3毫秒时产生突触后反应的易化。这一发现表明，通常在配对刺激后发生的背角中间神经元的生理抑制在节段性肌阵挛中未出现。这可能表明背角中间神经元异常活跃，并参与了脊髓肌阵挛的病理生理过程。
