Table 2.
Optimized parameter estimates and predictions from the 3-state model depicted in Fig. 5
| CMPs | Bepridi l (μΜ) | 3-state model fitted parameters |
3-state model predictions | |||||
|---|---|---|---|---|---|---|---|---|
| Cross-bridge | Regulatory unit | |||||||
| f (s−1) | g (s−1) | kON (M−1 s−1) (36) | kOFF (s−1) | pCa50 | max force (norm.) | max kTR (s−1) | ||
| Ctrl | 0 | 11.8 | 8.3 | 1.84×108 | 1254.4 | 5.57 | 1.00 | 19.3 |
| HCM | 0 | 12.4 | 12.6 | 1.34×108 | 176.6 | 6.18 | 0.86 | 24.8 |
| Ctrl | 300 | 15.6 | 13.4 | 1.84×108 | 702.2 | 5.77 | 0.92 | 27.8 |
Best fit parameter estimates for three parameters (f, g and kOFF) were obtained using the Simplex method (see Methods section); values for kON were from measurements reported by Pinto et al. (36). These parameter sets were used to illustrate relations between kTR and steady-state, isometric force in Fig. 2F (solid lines in Fig. 2F); also see the figure for information on the influence of small deviations (+/− 2%) from the best fit parameter estimates on predicted kTR-force relations (dashed lines in Fig. 2F).