Experimental data recorded on NKA inhibited cells (open circles, mean ± STD) are compared to the calculated model solutions.

<p>Obtained model solutions are shown by solid lines with filled symbols for models 1–4 and dashed lines with open symbols for the simplified versions of the models (2s, 3s and 4s). The experimental data from respiration experiments: oxygen consumption rate recorded during titration with ADP (A) or titration with ATP (B); data from spectrophotometric experiments: total ATPase activity (C), and endogenous PK activity (D). In addition, since there is no endogenous PK activity in model 1, the rate of PKend calculated by model 1 is zero in D. Note that all of the models that take into account endogenous PK (models 2–4) produce similar fits with no model fit being conclusively superior to the others.