Figure 4.
Frequency-dependent regulation of transmitter release. Augmentation of synaptic transmission was examined by evoking ejps at different frequencies of nerve stimulation. WT displayed a smooth increase in ejp amplitudes during stimulation with a larger plateau amplitude at higher stimulus frequencies. Shab exhibited a jump in ejp amplitudes earlier, as frequency increased. Sh exhibited large ejps at the onset of repetitive stimulation, regardless of stimulus frequency. [Ca2+] = 0.1 mm. The number of muscles was 3–10 for each genotype.