Zealear David L, Rodriguez Ricardo J, Kenny Thomas, Billante Mark J, Cho Young, Billante Cheryl R, Garren Kurt C
Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University, Nashville, Tennessee 37232, USA.
J Neurophysiol. 2002 Apr;87(4):2195-9. doi: 10.1152/jn.00451.2001.
The effect of electrical stimulation of the denervated posterior cricoarytenoid (PCA) muscle on its subsequent reinnervation was explored in the canine. Eight animals were implanted with a planar array of 36 electrodes for chronic stimulation and recording of spontaneous and evoked electromyographic (EMG) potentials across the entire fan-shaped surface of a muscle pair. Normative EMG data were recorded from each electrode site before unilateral nerve section, and from the innervated partner after nerve section. After randomizing the animals to experimental and control groups, the right recurrent laryngeal nerve innervating the PCA abductor muscle and its adductor antagonists was sectioned and reanastomosed. The PCA muscle in four experimental animals was continuously stimulated during the 11-mo experiment, using a 1-s, 30-pps, biphasic pulse train composed of 1-ms pulses 2-6 mA in amplitude and repeated every 10 s. The remaining four animals served as nonstimulated controls. Appropriate reinnervation by native inspiratory motoneurons was indexed behaviorally by the magnitude of vocal fold opening and electromyographically by the potential across all electrode sites. Inappropriate reinnervation by foreign adductor motoneurons was quantitated by recording EMG potentials evoked reflexly by stimulation of sensory afferents of the laryngeal mucosa. All four experimental animals showed a greater level of correct PCA muscle reinnervation (P < 0.0064) and a lesser level of incorrect reinnervation (P < 0.0084) than the controls. Direct muscle stimulation also appeared to enhance the overall magnitude of reinnervation, but the effect was not as strong (P < 0.113). These findings are consistent with a previous report and suggest that stimulation of a mammalian muscle may profoundly affect its receptivity to reinnervation by a particular motoneuron type.
在犬类动物中探究了对去神经支配的环杓后肌（PCA）进行电刺激对其后续再支配的影响。八只动物植入了一个由36个电极组成的平面阵列，用于对一对扇形肌肉表面进行慢性刺激并记录自发和诱发的肌电图（EMG）电位。在单侧神经切断前，从每个电极部位记录正常的EMG数据，神经切断后从受支配的对侧肌肉记录。将动物随机分为实验组和对照组后，切断并重新吻合支配PCA外展肌及其内收拮抗肌的右侧喉返神经。在为期11个月的实验中，对四只实验动物的PCA肌肉进行持续刺激，使用由1毫秒脉冲组成的1秒、30次/秒、双相脉冲序列，幅度为2 - 6毫安，每10秒重复一次。其余四只动物作为未刺激的对照。通过声带张开的幅度在行为上对由原生吸气运动神经元进行的适当再支配进行指标化，并通过所有电极部位的电位在肌电图上进行指标化。通过记录刺激喉黏膜感觉传入神经反射诱发的EMG电位，对由外来内收运动神经元进行的不适当再支配进行定量。与对照组相比，所有四只实验动物均表现出更高水平的正确PCA肌肉再支配（P < 0.0064）和更低水平的错误再支配（P < 0.0084）。直接肌肉刺激似乎也增强了再支配的总体幅度，但效果不如前者显著（P < 0.113）。这些发现与之前的一份报告一致，并表明对哺乳动物肌肉的刺激可能会深刻影响其对特定运动神经元类型再支配的接受能力。
