Figure 7.

Impact of pN-Bleb on Ca²⁺ sensitivity and isometric force. (A) Three panels showing tension-pCa plots for samples of chemically permeabilized human myocardium activated in solutions with pCa values ranging from 9.0 to 4.5. The control (gray) data points show force values measured in the presence of 1.33% DMSO. The red, green, and blue data points show force measured in 1.33% DMSO plus 1, 10, or 50 μM pN-Bleb. All force values are normalized to the force measured in pCa 4.5 solution in DMSO with 0 pN-Bleb. Different preparations were used to test each drug concentration. (B) The Ca²⁺ sensitivity represented by pCa₅₀. Bars show mean ± SEM pCa₅₀ values measured in the presence of 1, 10, or 50 μM pN-Bleb. Post-hoc tests show the results of a linear mixed model statistical analysis as described in the main text. (C) The Hill coefficient results are displayed as in (B).