Frank E, Gautvik K, Sommerschild H
Acta Physiol Scand. 1975 Sep;95(1):66-76. doi: 10.1111/j.1748-1716.1975.tb10026.x.
The number of acetylcholine receptors at normal and denervated end-plated in rat soleus muscles was studied using the binding of [125A] alpha-bungarotoxin as a quantitative assay. Normal end-plates bound several thousand times as much toxin as equal areas of extra-synaptic muscle membrane. After short-term denervation (up to 2.4 weeks) the extrajunctional binding increased, but there was no change in specific binding to the motor end-plate. Denervation for longer periods (up to 7 weeks) reduced binding sites at the end-plate by up to 60-70%. Direct electrical stimulation of these muscles for the entire period of denervation did not prevent the loss of junctional binding sites even though it was adequate to abolish the increase in extrajunctional toxin binding. In contrast, denervated end-plates on muscle fibres cross-innervated by a foreign nerve at a distant location continued to bind normal amounts of toxin for over four months.
利用[125A]α-银环蛇毒素的结合作为定量测定方法，研究了大鼠比目鱼肌正常和去神经支配终板处乙酰胆碱受体的数量。正常终板结合的毒素量是同等面积突触外肌膜的数千倍。短期去神经支配（长达2.4周）后，接头外结合增加，但与运动终板的特异性结合没有变化。去神经支配更长时间（长达7周）会使终板处的结合位点减少多达60 - 70%。在整个去神经支配期间对这些肌肉进行直接电刺激，即使足以消除接头外毒素结合的增加，也不能阻止接头结合位点的丧失。相反，由远处的外来神经交叉支配的肌纤维上的去神经支配终板在四个多月的时间里继续结合正常量的毒素。
