Column 1 refers to the multi-compartment model of Fig. 4, which includes ATP and is considered the reference point for the comparisons. Part B of column 1 gives the parameters of the release waveform used to drive this model. In part A, the “actual” peak is the value of this waveform integrated from time zero to infinity, whereas the “estimated” peak refers to the peak value of the waveform obtained as the sum of Δ[Ca²⁺], Δ[CaTrop], Δ[CaParv], and, in the case of column 1, Δ[CaATP]. (These waveforms reach a peak and then decay because of SR Ca²⁺ pumping.) Columns 2 and 3 give release parameters as estimated by the single-compartment model without ATP if driven by the multi-compartment simulation of spatially averaged Δ[Ca²⁺] (which was calculated for each of the indicators; see text). Column 2 is for a furaptra simulation (assumed K_d,Ca of furaptra is 70 μM for the multi-compartment simulation and 98 μM for the single-compartment reestimation of Δ[Ca²⁺]; see results). Column 3 is analogous to column 2 but is for a PDAA simulation (assumed K_d,Ca of PDAA, 1 mM for both parts of the simulation).