Figure 7. Comparison of the first 0.2 s of the time course of the change in I_1,1 obtained in the presence and absence of Ca²⁺.

The data and exponential traces obtained by regression to the data, shown in Figs 4 and 5, are superimposed. The data were normalised so that the rigor intensities in the presence and absence of Ca²⁺ were identical. It can be seen that the amplitude of the initial changes in the absence of Ca²⁺ is greater than that in the presence of Ca²⁺, pointing to truncation of the underlying process in the latter case, but the changes in the initial 10 ms overlap.