Table 2.
Isometric muscle function of mice extensor digitorum longus and soleus muscles with and without exposure to low (26 cGy) radiation by microcomputed tomography scanning
| EDL | SOL | |||
|---|---|---|---|---|
| CON | RAD | CON | RAD | |
| P t (mN) | 52 ± 6 | 70 ± 7 | 25 ± 2 | 24 ± 1 |
| P o (mN) | 350 ± 31 | 406 ± 18 | 229 ± 22 | 228 ± 11 |
| P t/CSA (mN/mm2) | 23 ± 2 | 31 ± 3 | 19 ± 2 | 18 ± 1 |
| P o/CSA (mN/mm2) | 156 ± 13 | 181 ± 8 | 172 ± 15 | 168 ± 10 |
| P t:P o | 0.15 ± 0.01 | 0.17 ± 0.01 | 0.11 ± 0.01 | 0.11 ± 0.01 |
| TPT(msec) | 17 ± 0.3 | 17 ± 0.3 | 43.0 ± 1.5 | 40.0 ± 1.5 |
| 1/2 RT(msec) | 17 ± 0.5 | 17 ± 0.8 | 42.3 ± 2.3 | 40.8 ± 3.1 |
| TPT/P t (msec/mN) | 0.4 ± 0.1 | 0.3 ± 0.0 | 1.8 ± 0.2 | 1.4 ± 0.3 |
| 1/2 RT/P t (msec/mN) | 0.4 ± 0.1 | 0.3 ± 0.0 | 1.8 ± 0.2 | 1.4 ± 0.3 |
| +dP/dt (mN/msec) | 3.2 ± 0.4 | 4.3 ± 0.4 | 1.1 ± 0.1 | 1.0 ± 0.1 |
| −dP/dt (mN/msec) | 1.9 ± 0.2 | 2.7 ± 0.3 | 0.4 ± 0.0 | 0.4 ± 0.0 |
Values are mean ± SEM. n = 6. EDL, extensor digitorum longus; SOL, soleus; CON, no radiation exposure; RAD, radiation exposure; P t, peak twitch force; P o, peak tetanic force; CSA, cross‐sectional area; P t:P o, twitch to tetanus ratio; TPT, time‐to‐peak tension; 1/2 RT, half‐relaxation time; +dP/dt, rate of force development; −dP/dt, rate of force relaxation.