Table 3.
Calcium parameters for isolated myofibers
| Calcium parameters | C57BL/6 WT | KO | FVB WT | TG | ||||
| Calcium transient parameters | ||||||||
| Time (s) | 0 | 60 | 0 | 60 | 0 | 60 | 0 | 60 |
| BG (AU) | 22.6 ± 0.9 | 25.0 ± 1.2 | 20.5 ± 0.6 (P = NS) | 21.7 ± 0.8 (P < 0.05) | 20.0 ± 0.9 | 21.3 ± 1.0 | 18.9 ± 1.5 (P = NS) | 18.7 ± 1.4 (P = NS) |
| F/F0 | 7.5 ± 0.2 | 5.6 ± 0.3 | 8.3 ± 0.4 (P = NS) | 7.2 ± 0.4 (P < 0.05) | 7.7 ± 0.4 | 5.9 ± 0.4 | 8.4 ± 0.3 (P = NS) | 6.9 ± 0.2 (P < 0.05) |
| Time to peak (ms) | 8.2 ± 0.2 | 8.3 ± 0.1 | 8.3 ± 0.01 (P = NS) | 8.6 ± 0.2 (P = NS) | 8.8 ± 0.3 | 8.9 ± 0.3 | 8.9 ± 0.3 (P = NS) | 8.8 ± 9.2 (P = NS) |
| T50 (ms) | 11.1 ± 0.5 | 11.1 ± 0.6 | 11.4 ± 0.7 (P = NS) | 12.3 ± 0.7 (P = NS) | 9.4 ± 0.6 | 9.9 ± 0.9 | 8.5 ± 0.4 (P = NS) | 8.5 ± 0.3 (P = NS) |
| Resting cytosolic calcium | ||||||||
| Time (s) | 0 | 60 | 0 | 60 | 0 | 60 | 0 | 60 |
| Intensity ratio 340 nm/380 nm | 0.94 ± 0.04 | 0.99 ± 0.03 | 0.90 ± 0.01 (P = NS) | 0.99 ± 0.01 (P = NS) | 0.97 ± 0.02 | 1.05 ± 0.02 | 0.94 ± 0.03 (P = NS) | 1.05 ± 0.02 (P = NS) |
Summary statistics for calcium transient parameters of background intensity (BG), spatial average of Ca2+ fluorescence (F/F0), time to peak, and 50% decay (T50), as well as ratiometric quantification of resting cytosolic calcium concentration (intensity ratio 340 nm/380 nm) are displayed (p-values are for KO or TG vs. corresponding WT parameters using Student’s t test). For calcium transient parameters, n = 25, 19, 8, and 14 for C57BL/6 WT, KO, FVB WT, and TG, respectively. For resting cytosolic calcium, n = 6, 17, 13, and 11 for C57BL/6 WT, KO, FVB WT, and TG, respectively.