Summary of mechanical properties in cTnIAla5/MyBP-C−/− skinned myocardium before (- cMyBP-C), after reconstitution with purified cMyBP-C (+ cMyBP-C), and after reconstitution with purified cMyBP-C and PKA treatment (+ cMyBP-C/+ PKA)
| Treatment group | Resting force | Maximum Ca2+-activated force | Hill coefficient (nH) | Ca2+ sensitivity of force (pCa50) | Maximum rate of force redevelopment | Minimum rate of force redevelopment |
| mN/mm2 | mN/mm2 | s−1 | s−1 | |||
| cTnIAla5/cMyBP-C−/− | ||||||
| (−) cMyBP-C (n = 7) | 0.83 ± 0.15 | 14.70 ± 1.91 | 2.90 ± 0.08 | 5.49 ± 0.02 | 35.05 ± 2.52 | 2.28 ± 0.18 |
| (+) cMyBP-C (n = 6) | 1.26 ± 0.18 | 16.16 ± 1.08 | 3.28 ± 0.13a | 5.51 ± 0.01 | 15.37 ± 2.00a | 1.26 ± 0.22a |
| (+) cMyBP-C (+) PKA (n = 6) | 1.03 ± 0.29 | 12.68 ± 0.62 | 2.73 ± 0.09b | 5.44 ± 0.01ab | 22.64 ± 2.50ab | 3.48 ± 0.65b |
| Treatment group | Resting force | Maximum Ca2+-activated force | Hill coefficient (nH) | Ca2+ sensitivity of force (pCa50) | Maximum rate of force redevelopment | Minimum rate of force redevelopment |
| mN/mm2 | mN/mm2 | s−1 | s−1 | |||
| cTnIAla5/cMyBP-C−/− | ||||||
| (−) cMyBP-C (n = 7) | 0.83 ± 0.15 | 14.70 ± 1.91 | 2.90 ± 0.08 | 5.49 ± 0.02 | 35.05 ± 2.52 | 2.28 ± 0.18 |
| (+) cMyBP-C (n = 6) | 1.26 ± 0.18 | 16.16 ± 1.08 | 3.28 ± 0.13a | 5.51 ± 0.01 | 15.37 ± 2.00a | 1.26 ± 0.22a |
| (+) cMyBP-C (+) PKA (n = 6) | 1.03 ± 0.29 | 12.68 ± 0.62 | 2.73 ± 0.09b | 5.44 ± 0.01ab | 22.64 ± 2.50ab | 3.48 ± 0.65b |
Data are means ± SE. Resting force was measured at pCa 9.0. Maximum force and the rate constant of force redevelopment (ktr) were measured at pCa 4.5. Minimum ktr was measured at ∼10% of maximum force. pCa50 and nH values were derived by fitting the force–pCa relationships to a Hill equation.
Significantly different from values recorded in cTnIAla5/cMyBP-C−/− skinned myocardial preparations (−cMyBP-C).
Significantly different from values recorded in cTnIAla5/cMyBP-C−/− skinned myocardial preparations reconstituted with purified cMyBP-C (+cMyBP-C).