Figure 4.

Efferent Ca²⁺ signals are affected by blocking cisternal ATPases, but not by modulators of RyRs. A, Mean synaptic responses (black, 95% confidence intervals in gray) and Ca²⁺ transients (red, 95% confidence intervals in light red) during a 300-ms electrical stimulation at 20, 40, and 80 Hz before and after perfusion of thapsigargin (x scale bar: 250 ms; y scale bar: 50 A.U. and 100 pA). B, Peak of Ca²⁺ transients (as ΔF). C, Charge of synaptic responses. D, Duration of Ca²⁺ transients (as FWHM). Inset, Baseline fluorescence signal before and after perfusion of thapsigargin. E, Synaptic currents (mean, black, confidence intervals in gray) and Ca²⁺ transients (red, confidence interval in light red) obtained during efferent fiber stimulation (300 ms, 80 Hz), using an intracellular solution containing vehicle (DMSO), RyR blockers (ryanodine 100 μm or dantrolene 30 μm), or a RyR agonist (ryanodine 1 μm; x scale bar: 250 ms; y scale bar: 50% and 100 pA). F, Baseline fluorescence for each condition. Duration (FWHM; G) and maximal fluorescence signal (as ΔF/F₀; H) for each intracellular solution. Bar plots are mean ± SEM. Wilcoxon signed-rank test; *p < 0.05.