Cam increases during and following Ca2+ entry and decreases during late clearance. Rhod-2 was loaded as its AM ester and Calcium Green Dextran by whole cell dialysis. Calcium Green fluorescence observed in the on-cell patch clamp configuration was subtracted before calibration of signals simultaneously recorded from a single cell 5 min after the whole-cell configuration was established. (A) Cam and Cac responses to a 500-ms depolarization applied at the arrow. The final portion of Cac recovery is shown (dots) on a 20× expanded scale. (B) The initial portions of Cam (open circle) and Cac (open triangle) traces from A are aligned in time to the depolarizing stimulus. (C) The relationship of Cam to Cac during this response to stimulus and subsequent recovery; a closed diamond marks the Cam and Cac values at the termination of stimulus. The curved arrow indicates the approximate nonlinear time course; the lines divide elapsed time into segments of ~0.5, 5, and 50 s duration.