Josephson R K, Malamud J G, Stokes D R
School of Biological Sciences, University of California at Irvine, Irvine, CA 92697, USA.
J Exp Biol. 2000 Sep;203(Pt 18):2713-22. doi: 10.1242/jeb.203.18.2713.
The asynchronous muscles of insects are characterized by asynchrony between muscle electrical and mechanical activity, a fibrillar organization with poorly developed sarcoplasmic reticulum, a slow time course of isometric contraction, low isometric force, high passive stiffness and delayed stretch activation and shortening deactivation. These properties are illustrated by comparing an asynchronous muscle, the basalar flight muscle of the beetle Cotinus mutabilis, with synchronous wing muscles from the locust, Schistocerca americana. Because of delayed stretch activation and shortening deactivation, a tetanically stimulated beetle muscle can do work when subjected to repetitive lengthening and shortening. The synchronous locust muscle, subjected to similar stimulation and length change, absorbs rather than produces work.
肌肉电活动与机械活动不同步、肌原纤维组织且肌浆网发育不良、等长收缩的时间进程缓慢、等长力低、被动僵硬度高以及拉伸激活和缩短失活延迟。通过将一种异步肌肉（变色花金龟的基翼飞行肌）与美洲沙漠蝗的同步翅肌进行比较，可以说明这些特性。由于拉伸激活和缩短失活延迟，受到强直刺激的甲虫肌肉在经历重复的拉长和缩短时能够做功。而受到类似刺激和长度变化的同步蝗虫肌肉则吸收能量而非产生功。
