Fig. 7: Regulation of Ca2+ release at internal sites.
a, Using highly inclined and laminated optical sheet imaging, correlative Ca2+ and RyR imaging was performed within the cell interior. Scale bars, 800 nm. b–e, As observed on the cell surface (see previous figures), multirelease Ca2+ sparks at internal sites exhibited greater movement than single-release events (b), and tended to be larger (c), with slower kinetics (d,e). f,g, ISO treatment markedly increased spark rate (f), but not the proportional occurrence of multirelease sparks (see main text) or RyR cluster sizes (g, estimated by tight RyR packing within thresholded 2D area). Data are presented as mean ± s.e.m. Differences between groups were tested with two-tailed linear mixed models with Tukey post hoc correction for multiple comparisons. *P < 0.05, **P < 0.01, ***P < 0.001. Please refer to Source data for exact P values and n values.
