Linden D C, Newton M W, Grinnell A D, Jenden D J
Exp Neurol. 1983 Sep;81(3):613-26. doi: 10.1016/0014-4886(83)90330-8.
The amount of acetylcholine (ACh) and choline (Ch) in normal and denervated rat extensor digitorum longus (EDL) muscles, as well as that released spontaneously from these muscles, was determined by an extremely sensitive gas chromatographic-mass spectrometric assay method. We found decreases in ACh content and spontaneous, resting ACh release as early as 8 h after denervation. The ACh content decreased to a plateau of 30% of control by 11 h; ACh release attained a plateau of 50% of control several hours later. These results showed that in denervated EDL muscles ACh content and spontaneous release (measured biochemically) decreased before nerve-evoked and spontaneous quantal release (measured physiologically) ceased at most synapses. The rapid reduction in ACh, or possibly in other substances that may be released with ACh, may be an important factor in initiating postsynaptic degenerative changes after nerve transection. Choline content and choline resting release increased significantly at both 1 and 3 days after nerve transection. These increases may be related to onset of postsynaptic neuromuscular degenerative changes.
采用一种极其灵敏的气相色谱 - 质谱分析法，测定了正常和去神经支配的大鼠趾长伸肌（EDL）中乙酰胆碱（ACh）和胆碱（Ch）的含量，以及这些肌肉自发释放的ACh和Ch的量。我们发现，去神经支配后8小时，ACh含量以及静息状态下的ACh自发释放量就开始下降。到11小时时，ACh含量降至对照组的30%并趋于平稳；数小时后，ACh释放量达到对照组的50%并趋于平稳。这些结果表明，在去神经支配的EDL肌肉中，在大多数突触处神经诱发的和自发的量子释放（通过生理学方法测量）停止之前，ACh含量和自发释放量（通过生化方法测量）就已经下降。ACh的快速减少，或者可能是与ACh一起释放的其他物质的快速减少，可能是神经横断后引发突触后退行性变化的一个重要因素。在神经横断后的第1天和第3天，胆碱含量和胆碱静息释放量均显著增加。这些增加可能与突触后神经肌肉退行性变化的发生有关。
