Fig. 3.
TnTA30V-mediated impact on steady-state maximal tension in α- and β-MHC fibers. Measurements of steady-state tension were made in muscle fibers at maximal Ca2+ activation (pCa 4.3), as described previously (15, 45). The effect of TnTA30V on the force response (normalized to the cross-sectional area) during isometric contraction at pCa 4.3 in α-MHC (A) and β-MHC fibers (B) is shown. The effect of TnTA30V on maximal tension in α- and β-MHC fibers (C). Data for each group are expressed as means ± SE. Statistical differences were analyzed for TnTA30V, relative to TnTWT, using two-way ANOVA and post hoc Fisher’s LSD tests (**P < 0.01; ***P < 0.001). The number of fibers measured (from 3 hearts) were as follows: TnTWT + α-MHC (n = 12), TnTA30V + α-MHC (n = 14), TnTWT + β-MHC (n = 11), and TnTA30V + β-MHC (n = 12).