Long-term Depression at the Crayfish Fast Extensor Neuromuscular Junction Has Presynaptic and Postsynaptic Components

摘要: We used measurements of excitatory junction potential (EJP) amplitude variance to explore whether long-term depression (LTD) induced by low-frequency stimulation at the crayfish superficial fast extensor muscle was pre- or post-synaptically expressed. LTD and measured intermittent low frequency (0.5 Hz) over course several hours. This appeared have three stages. During first stage (the 15 minutes 0.5 Hz stimulation), EJPs depressed around 60% their original amplitude, an effect that involve a decrease in quantal content. second (15-100 stimulation) EJP continued depress slowly, which seems involved release probability increase final stage, (100-205 plateaued with apparent It should be noted this analysis performed under assumption releasable neurotransmitter vesicle pool size remained constant experiment.