Buffelli M, Pasino E, Cangiano A
Dipartimento di Scienze Neurologiche e della Visione, University of Verona, Italy.
J Muscle Res Cell Motil. 1997 Dec;18(6):683-95. doi: 10.1023/a:1018687923929.
The effects of long lasting (4-5 weeks) nerve conduction block and denervation were compared by investigating contractile, morphological and histochemical properties of slow (soleus) and fast (EDL) rat skeletal muscles. The block was based on improved perfusion techniques of the sciatic nerve with a tetrodotoxin (TTX) solution delivered at doses adequate to obtain maximal effects in the muscles. The TTX-inactivated axons retained normal histological and physiological properties such as the ability to evoke full contractile responses, to regenerate, and to completely reinnervate muscle. In spite of their intact innervation or of their full reinnervation, the TTX-paralysed muscles underwent weight loss, fibre atrophy and reduction in force, output quantitatively indistinguishable from those following denervation. The same was true for all other contractile parameters tested, that is, twitch speed, twitch to tetanus ratio, post-tetanic potentiation, endurance, and fibre type composition. The results indicate the fundamental role of activity as a regulatory signal for muscle contractile properties, while they do not support the notion of a participation of chemical, activity-independent factors in this regulation.
通过研究大鼠慢肌（比目鱼肌）和快肌（趾长伸肌）的收缩、形态和组织化学特性，比较了持久（4 - 5周）神经传导阻滞和去神经支配的影响。该阻滞基于改进的坐骨神经灌注技术，使用河豚毒素（TTX）溶液，以足以在肌肉中获得最大效应的剂量给药。TTX失活的轴突保留了正常的组织学和生理学特性，如引发完全收缩反应、再生以及完全重新支配肌肉的能力。尽管TTX麻痹的肌肉具有完整的神经支配或完全重新支配，但它们仍出现体重减轻、纤维萎缩和力量下降，其输出在数量上与去神经支配后的情况无法区分。对于所有其他测试的收缩参数，即抽搐速度、抽搐与强直收缩比率、强直收缩后增强、耐力和纤维类型组成，情况也是如此。结果表明活动作为肌肉收缩特性调节信号的基本作用，同时不支持化学的、与活动无关的因素参与这种调节的观点。
