Misler S, Hurlbut W P
Proc Natl Acad Sci U S A. 1983 Jan;80(1):315-9. doi: 10.1073/pnas.80.1.315.
At many synapses, previous activity increases the amount of transmitter released by a single action potential. This potentiation of transmitter release is usually attributed to the local accumulation of the calcium ions that cross the axolemma during an action potential. We found that potentiated transmitter release can be observed at frog neuromuscular junctions after periods of repetitive stimulation in Ca2+-free solutions, if Ca2+ is restored after the tetanus. Potentiation is greater and more prolonged, the lower the level of extracellular K+. This component of potentiation may be due to Ca2+ that accumulates within the terminal in exchange for intracellular Na+.
在许多突触处，先前的活动会增加单个动作电位释放的神经递质数量。递质释放的这种增强通常归因于动作电位期间穿过轴膜的钙离子的局部积累。我们发现，在无钙溶液中进行重复刺激后，如果在强直刺激后恢复钙离子，在青蛙神经肌肉接头处可以观察到递质释放增强。细胞外钾离子水平越低，增强作用越大且持续时间越长。这种增强成分可能是由于钙离子在终末内积累以交换细胞内钠离子所致。
