Buchthal F
Acta Physiol Scand Suppl. 1982;502:5-18.
Sensory potentials were evoked by tactile stimuli to the dorso-lateral aspect of the foot and recorded via a near nerve electrode from the sural nerve. The averaged potential contained a burst of 6-8 components each 0.3-1.0 microV and a few later components. The averaged potential was reproducible and its time integral was used as a gauge of the size of the response. That the potential was a nerve action potential was indicated by (i) the diminution in amplitude with increasing distance of the electrode from the nerve, (ii) by the reversible abolition of the potential during local anaesthesia of the skin and the subcutaneous tissue and (iii) during anoxia. Fractionate local anaesthesia of the skin demonstrated that the response mainly originated from the activation of Pacinian corpuscles. The innervation area divided by the number of large myelinated fibres in the distal cutaneous branch of the sural nerve gave 10-20 mechanoreceptive units per cm2, one tenth of the density on the index finger. The shortest latency of the potential evoked by a tactile stimulus was 0.5-1.0 ms longer than the latency of the potential evoked by an electrical stimulus. The conduction velocity of the response evoked by a tactile stimulus was slower in the distal than in the proximal part of the nerve. This difference did not appear in the plot of potentials evoked by electrical stimuli probably because the electrical stimulus circumvents the distal portion of the nerve fibres.
通过对足部背外侧进行触觉刺激来诱发感觉电位，并通过腓肠神经附近的电极进行记录。平均电位包含一阵6 - 8个成分，每个成分0.3 - 1.0微伏，以及一些较晚出现的成分。平均电位具有可重复性，其时间积分被用作反应大小的衡量指标。该电位为神经动作电位的依据如下：(i) 随着电极与神经距离增加，振幅减小；(ii) 在皮肤和皮下组织局部麻醉期间以及 (iii) 在缺氧期间，电位可逆性消失。皮肤的分次局部麻醉表明，该反应主要源于环层小体的激活。将腓肠神经远端皮支的支配区域除以其中大的有髓纤维数量，得出每平方厘米有10 - 20个机械感受单位，是食指上密度的十分之一。触觉刺激诱发的电位最短潜伏期比电刺激诱发的电位潜伏期长0.5 - 1.0毫秒。触觉刺激诱发的反应在神经远端的传导速度比近端慢。在电刺激诱发的电位图中未出现这种差异，可能是因为电刺激绕过了神经纤维的远端部分。
