Figure 2.

AITC increases fractional shortening, maximum velocity of shortening and maximum velocity of relengthening in CMs. Overlays of individual cell shortening and relengthening events illustrating the dose-dependent effects of AITC (1–300 μmol/L) on fractional shortening are depicted in panel A. Representative overlays assessing changes in sarcomere length normalized to peak height (set at 100%) and aligned at initiation of stimulus or at peak shortening to illustrate dose-dependent changes in timing of shortening and relengthening are depicted in panels C and E, respectively. Summarized data for panels A (fractional shortening), C (maximal velocity of shortening) and E (maximal velocity of relengthening) are depicted in panels B, D and F, respectively. Results are expressed as percent of steady-state baseline control (Ctrl) value set at 100%. Changes in fractional shortening were measured as percent of sarcomere length. Changes in velocity were measured in micrometers/sec. * P < 0.05 compared with Ctrl. n = 20 cells from 6 hearts.