Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0570, Japan.
Department of Bioimaging Center, Kitasato University School of Medicine, Sagamihara, Japan.
Muscle Nerve. 2018 Mar;57(3):466-472. doi: 10.1002/mus.25754. Epub 2017 Aug 8.
This study assesses the effect of radial extracorporeal shock wave (rESW) exposure on neuromuscular transmission and neuromuscular junction (NMJ) morphology.
We applied 2,000 rESWs at 0.18 mJ/mm and a frequency of 15 Hz to the right calf of male rats, measured the compound muscle action potential (CMAP), and examined NMJ morphology using electron microscopy. Left calf muscles were used as controls.
rESW exposure significantly reduced CMAP amplitude without delayed latency in exposed muscles compared with controls. All rESW-exposed muscles exhibited NMJs with irregular end plates. Mean interjunctional fold interval was significantly increased compared with controls. However, axon terminals and muscle fibers surrounding NMJs with irregular end plates were unchanged.
This localized destruction of end plates may be caused by differences in acoustic impedance induced by the density of acetylcholine receptors. These results provide a possible mechanism for the effectiveness of rESW treatment for spasticity and dystonia. Muscle Nerve 57: 466-472, 2018.
本研究评估了径向体外冲击波（rESW）暴露对神经肌肉传递和神经肌肉接头（NMJ）形态的影响。
我们向雄性大鼠的右小腿施加 2000 次 rESW，频率为 15 Hz，强度为 0.18 mJ/mm，测量复合肌肉动作电位（CMAP），并使用电子显微镜检查 NMJ 形态。左小腿肌肉用作对照。
与对照组相比，rESW 暴露后，暴露肌肉的 CMAP 幅度显著降低，潜伏期无延迟。所有 rESW 暴露的肌肉均表现出不规则终板的 NMJ。与对照组相比，平均连接褶皱间隔显著增加。然而，围绕不规则终板的 NMJ 的轴突末端和肌肉纤维没有变化。
这种终板的局部破坏可能是由乙酰胆碱受体密度引起的声阻抗差异引起的。这些结果为 rESW 治疗痉挛和肌张力障碍的有效性提供了一种可能的机制。肌肉神经 57: 466-472, 2018.
