Fluorescence and flux in WT cells exposed to 0 Ca. (A) Fluorescence transients in response to the depolarizing pulse shown. Traces in green, cyan, and red are for the same cell after increasing times of exposure to 0 Ca (keyed in B). The record in blue is from a different cell in reference solution. Note that the amplitude of transients progressively falls and their kinetics becomes increasingly similar to that of the dCasq-null in Fig. 2. (B) $R•(t)$⁠, calculated from records in A, showing that in 0 Ca records lose the shoulder, characteristic of the WT in reference solution, becoming progressively similar to flux in dCasq-null cells. This is demonstrated in C, where the records in 0 Ca from B are scaled to match the peak of the $R•(t)$ from the dCasq-null example in Fig. 2. ID: WT in reference, 122206d_26; WT in 0 Ca, 052209b_9, 10, 11. For calculations of flux, [EGTA] in the 0 Ca example was assumed to enter the cell according to a saturating exponential of τ = 40 min.