Figure 4.

Sample variances and means obtained for test ΔC_m are positively correlated. (A) A plot of the trend-corrected sample variances versus their corresponding means shown in Fig. 3 (10-ms depolarizations, bin-size = 4). Both measures were correlated for test ΔC_m (circles). The regression line had a slope of ≈1.0 fF. There was no correlation between variances and means in the case of control ΔC_m (squares). (B) Sample variances (trend-corrected) and means calculated from the same ΔC_m data with an analysis bin-size of 8. The larger bin slightly reduced the scatter, but again yielded a slope of the regression line of ≈1.0 fF. (C) An analogous plot for the analysis of an experiment where 100-ms depolarizations were repetitively applied (bin-size = 4, symbols as used above). The slope of the regression line fitted to the test data was 1.6 fF.