Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142, Japan.
Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142, Japan.
Acta Histochem. 2014 Jun;116(5):936-42. doi: 10.1016/j.acthis.2014.03.006. Epub 2014 Apr 16.
The influence of electrical stimulation on calpain and ubiquitin-proteasome systems was examined in the denervated and unloaded tibialis anterior muscles of male Wistar rats. Animals were divided into 5 groups: control, denervation, denervation plus electrical stimulation, unloading, and hindlimb unloading plus electrical stimulation groups. Due to denervation and unloading for 14 days, muscle atrophy markedly occurred in the denervated and unloading animals, and the atrophy in the former was significantly more severe than that in the latter. In the denervated muscle, the atrophy was significantly attenuated by the electrical stimulation, but not in the unloaded muscle. Overexpression of calpain-2 and ubiquitinated proteins was observed only in denervated muscles. In the unloaded animals, though the expression level of calpain-2 appeared to be slightly higher than that in the control, the expression level of ubiquitinated proteins was almost the same as that in the control. The overexpression of calpain-1, calpain-2, and ubiquitinated proteins in the denervated muscle was inhibited by the electrical stimulation. However, there was no difference in these expressions between the unloaded and unloaded plus electrical stimulation groups. The mechanism of the preventive effect of the electrical stimulation on muscle atrophy might differ between the denervated and unloaded muscles.
电刺激对失神经和去负荷的比目鱼肌中钙蛋白酶和泛素-蛋白酶体系统的影响进行了研究。雄性 Wistar 大鼠被分为 5 组：对照组、去神经组、去神经加电刺激组、去负荷组和去负荷加电刺激组。由于失神经和去负荷 14 天，失神经和去负荷动物的肌肉明显萎缩，前者的萎缩程度明显比后者严重。在失神经肌肉中，电刺激明显减轻了萎缩，但在去负荷肌肉中没有。只有在失神经肌肉中观察到钙蛋白酶-2 和泛素化蛋白的过表达。在去负荷动物中，尽管钙蛋白酶-2 的表达水平似乎略高于对照组，但泛素化蛋白的表达水平与对照组几乎相同。电刺激抑制了失神经肌肉中钙蛋白酶-1、钙蛋白酶-2 和泛素化蛋白的过表达。然而，去负荷和去负荷加电刺激组之间这些表达没有差异。电刺激对肌肉萎缩的预防作用的机制在失神经和去负荷肌肉中可能不同。
