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Updated: Aug 19, 2026

Historical View and Physiology Demonstration at the NMJ of the Crayfish Opener Muscle
Published on: November 9, 2009
Changes in statistical parameters during facilitation at the crayfish neuromuscular junction
Abstract:
1. Transmitter release at excitatory neuromuscular junctions of the crayfish was studied at different frequencies of stimulation ranging from 1/sec to 20/sec.2. Over this frequency range the average number of quanta released per stimulus (m) increased with frequency by a factor of 6-7.3. Analysis of the fluctuations in quantal release using binomial statistics indicated that the increase in m was associated with increase in the average quantal release probability (p) at stimulation frequencies between 5/sec and 20/sec. Between 1/sec and 5/sec there was an apparent increase in the number of quanta available for release (n).
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