Aghi Krisha, Schultz Ryan, Stowers R Steven, Liu William YuChen, Mendonça Philipe R F, Li Rachel, Bakshinska Dariya, Newman Zachary L, Isacoff Ehud Y
Helen Wills Neuroscience Institute, UC Berkeley, Berkeley, CA 94720, USA.
Department of Microbiology & Cell Biology, Montana State University, PO Box 173520, Bozeman, MT 59717, USA.
Curr Biol. 2025 Jun 23;35(12):2881-2892.e6. doi: 10.1016/j.cub.2025.05.024. Epub 2025 Jun 3.
Synaptic strength can vary greatly between synapses. Optical quantal analysis at Drosophila glutamatergic motor neuron synapses shows that short-term plasticity also varies greatly between synapses, even those made by an individual motor neuron. Strong and weak synapses are randomly distributed in the motor neuron nerve terminal, as are facilitating and depressing synapses. Although synapses exhibit highly heterogeneous basal strength at low-action potential firing frequency and undergo varied plasticity when firing frequency increases, the overall distribution of strength across synapses remains remarkably constant due to a balance between the number of synapses that facilitate versus depress and to their degree of plasticity and basal synaptic weight. Constancy in transmitter release can ensure robustness across changing behavioral conditions.
突触强度在不同突触之间可能有很大差异。对果蝇谷氨酸能运动神经元突触进行的光学量子分析表明，短期可塑性在不同突触之间也有很大差异，即使是由单个运动神经元形成的突触也是如此。强突触和弱突触在运动神经元神经末梢中随机分布，易化性突触和抑制性突触也是如此。尽管突触在低动作电位发放频率下表现出高度异质性的基础强度，并且在发放频率增加时经历不同的可塑性变化，但由于易化性突触与抑制性突触的数量之间的平衡以及它们的可塑性程度和基础突触权重，突触强度的整体分布仍保持显著恒定。递质释放的恒定性可确保在不断变化的行为条件下的稳健性。
