Figure 8.

Kinetic parameters of burst activity of WT hRyR2 at various activating [Ca²⁺]_cyt. These are plotted as a scatter of means ± SEM (A–C) for individual channels and mean ± SEM for data points from all channels (D). Bursts were analyzed from seven individual single-channel recordings at 1 (red squares), 10 (green squares), 100 (blue squares), and 200 µM (black squares) Ca²⁺. As the duration of bursts increases with increasing [Ca²⁺]_cyt, for a given duration of recording, the total number of detected bursts decreases. For this analysis, 20–190 bursts were used for each channel at every [Ca²⁺]_cyt (A–C), and for D, a total of 300–720 interburst intervals for each [Ca²⁺]_cyt were detected and analyzed. (A and B) The relationship between P_o within burst and intraburst T_c and T_o, respectively, with increasing [Ca²⁺]_cyt. (C) The relationship of burst length and intraburst P_o with increasing [Ca²⁺]_cyt. (D) A bar chart shows the effect of increasing [Ca²⁺]_cyt on interburst intervals (T_interburst). Error bars, where not visible, are included within the dimensions of the squares (A–C) or bars (D).