| Group . | pCa50 . | nH . | Fmax (mN/mm2) . | Fmin (mN/mm2) . |
|---|---|---|---|---|
| WT + PKA | ||||
| Pre-OM | 5.77 ± 0.03 | 2.04 ± 0.06 | 17.44 ± 1.68 | 0.58 ± 0.04 |
| 1.0 µM OM | 5.99 ± 0.10 | 1.07 ± 0.07 (*, P = 0.02) | 13.54 ± 0.08 | 1.52 ± 0.08 |
| SA + PKA | ||||
| Pre-OM | 5.79 ± 0.02 | 2.13 ± 0.13 | 14.88 ± 0.33 | 1.54 ± 0.21 |
| 1.0 µM OM | 5.92 ± 0.08 | 1.52 ± 0.32 | 11.43 ± 2.77 | 2.19 ± 0.54 |
| Group . | pCa50 . | nH . | Fmax (mN/mm2) . | Fmin (mN/mm2) . |
|---|---|---|---|---|
| WT + PKA | ||||
| Pre-OM | 5.77 ± 0.03 | 2.04 ± 0.06 | 17.44 ± 1.68 | 0.58 ± 0.04 |
| 1.0 µM OM | 5.99 ± 0.10 | 1.07 ± 0.07 (*, P = 0.02) | 13.54 ± 0.08 | 1.52 ± 0.08 |
| SA + PKA | ||||
| Pre-OM | 5.79 ± 0.02 | 2.13 ± 0.13 | 14.88 ± 0.33 | 1.54 ± 0.21 |
| 1.0 µM OM | 5.92 ± 0.08 | 1.52 ± 0.32 | 11.43 ± 2.77 | 2.19 ± 0.54 |
pCa50, myofilament Ca2+ sensitivity; nH, cooperativity of force production; Fmax, maximal Ca2+-activated force measured at pCa 4.5; Fmin, Ca2+-independent force measured at pCa 9.0. Values are expressed as mean ± SEM. Data from multiple preparations from each heart were averaged, and six to seven myocardial preparations from three different hearts were used per group. *, Significantly different compared with the corresponding pre-OM group.