Figure 4
Model-predicted cooperative rate constants K1 (A) and Ka (B) vs. the total number of formed cross-bridges, [Ca•TnCA•M] + [TnCA•M] for all experimental groups before (left) and after (right) ischemia. Ischemia alone resulted in a decrease in the maximum estimated number of formed cross-bridges from 14.2 μM to 9.2 μM. The maximal estimated number of formed cross-bridges with dopamine and dobutamine were less than control before ischemia (7.3 μM and 11.8 μM, respectively) and greater than control after (10.6 μM and 12.7 μM, respectively) ischemia. After ischemia digoxin increased the maximum estimated number of formed cross-bridges (13.6 μM) compared to control.