Table 2.
Muscle peak twitch force
| Force | Time | C57BL/6 WT (n = 9) | KO (n = 10) | FVB WT (n = 15) | TG (n = 19) |
| min | |||||
| Specific peak force (mN/cm2) (P vs. WT) | 0 | 4,323 ± 259 | 5,465 ± 471 (P = NS) | 4,471 ± 188 | 4,638 ± 120 (P = NS) |
| Δ vs. baseline (P vs. WT) | 7 | −87 ± 59 (P = NS) | 280 ± 69 (P < 0.001) | −255 ± 53 | 9 ± 64 (P = 0.004) |
Peak twitch force of in situ TA muscle is measured at time 0 (baseline) and at 7-min duration of the 1-Hz isometric twitching protocol. KO and TG mice are compared with their respective C57BL/6 and FVB WT controls. Measurements at time 7 min are expressed as the mean of the difference between the peak force of each muscle at 7 min versus its own baseline force at time 0. TA muscle mass (in mg) is 50.2 ± 0.3, 49 ± 0.6, 49.2 ± 0.5, and 48.6 ± 0.23 for WT C57BL/6, KO, WT FVB, and TG, respectively (P = NS between KO or TG and their WT controls by Student’s t test), and L0 (in mm) is 15.50 ± 0.48, 15.90 ± 0.21, 14.71 ± 0.36, and 14.53 ± 1.0, respectively (P = NS between KO or TG and their WT controls using Student’s t test).