Table 5.

Results for rate of force development, 2πb, at maximal pCa 4.8 and submaximal pCa 5.75

2πb (s-1) at pCa 4.8	NTGβ	NTGβ,PKA	t/tβ	t/tβ,PKA	ANOVA
n	9	8	10	10
Pi (mM) = 0	7.98 ± 0.59	7.98 ± 0.63	10.98 ± 0.61	8.64 ± 0.62	Main effects
1	8.27 ± 0.54	9.60 ± 0.63	12.79 ± 0.79	11.49 ± 0.89	†MYBPC3, †Pi
2	8.46 ± 0.60	10.87 ± 0.73	14.51 ± 0.79	13.15 ± 1.10
3	9.23 ± 0.62	11.66 ± 1.03	16.54 ± 0.83	15.91 ± 1.31	Interactions
4	9.73 ± 0.84	12.61 ± 0.99	18.18 ± 0.84	18.60 ± 1.29	†Pi × MYBPC3
5	9.90 ± 0.84	13.70 ± 1.12	19.32 ± 0.84	19.78 ± 1.59	*Pi × PKA
8	10.72 ± 1.38	14.36 ± 1.28	21.70 ± 1.24	23.12 ± 1.63
12	12.71 ± 1.71	15.32 ± 1.40	23.48 ± 1.60	26.37 ± 1.69
Δ2πb/ΔPi	0.55 ± 0.10	0.92 ± 0.18	1.62 ± 0.17	2.23 ± 0.33	†MYBPC3, *PKA
2πb (s-1) at pCa 5.75
Pi (mM) = 0	8.01 ± 0.52	7.95 ± 0.84	9.85 ± 0.86	7.47 ± 0.66	Main effects
1	8.09 ± 0.54	9.71 ± 1.09	12.05 ± 1.04	8.92 ± 0.85	†MYBPC3, †Pi
2	9.58 ± 0.55	9.75 ± 1.34	13.17 ± 0.86	10.45 ± 0.92
3	9.48 ± 0.72	10.31 ± 1.51	14.57 ± 1.11	11.85 ± 1.01	Interactions
4	10.42 ± 0.61	11.66 ± 1.59	15.71 ± 1.42	12.84 ± 0.91	†Pi × MYBPC3
5	11.15 ± 0.66	12.20 ± 1.71	17.51 ± 1.35	13.09 ± 1.32
8	12.41 ± 1.00	15.00 ± 1.81	19.85 ± 1.37	16.43 ± 1.45
12	13.31 ± 1.26	16.88 ± 2.03	21.78 ± 1.64	16.61 ± 1.51
Δ2πb/ΔPi	0.68 ± 0.07	0.79 ± 0.19	1.41 ± 0.23	1.18 ± 0.20	†MYBPC3

Values are means ± SE; n, number of strips. The sensitivity of 2πb to Pi was calculated and denoted here as Δ2πb/ΔPi. Statistical results reflect repeated-measures ANOVA. Two-way ANOVA was then applied to Δ2πb/ΔPi. *P < 0.05, †P < 0.01. NTG_β, nontransgenic; t/t_β, transgenic lacking cMyBP-C; PKA, protein kinase A.