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Updated: Aug 18, 2026

Historical View and Physiology Demonstration at the NMJ of the Crayfish Opener Muscle
Published on: November 9, 2009
The effects of calcium and magnesium on statistical release parameters at the crayfish neuromuscular junction
Abstract:
1. Transmitter release at excitatory neuromuscular junctions of crayfish muscle was studied at low temperature by recording synaptic potentials with extracellular micro-electrodes.2. Increasing the Ca concentration in the bathing solution produced an increase in the average number of quanta released per nerve stimulus (m). Increasing the Mg concentration resulted in a decrease in m.3. Statistical analysis of fluctuations in the quantal release from trial to trial, assuming binomial statistics, indicated that both the changes in m were due to changes in the average quantal release probability (p).
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