Contractile properties of rainbow trout ventricle preparations at 0.5 Hz, before (basal) and 20 min after exposure to optimal concentrations of testosterone (T; 0.3 μmol l-1) in males and 17β-estradiol(E2; 1.0 nmol l-1) in females
| Contractile variable . | Males (basal) . | Males (steroid-treated) . | Females (basal) . | Females (steroid-treated) . |
|---|---|---|---|---|
| F (mN) | 8.9±1.3 | 13.2±1.7 | 8.1±1.4 | 12.6±1.5 |
| tp (ms) | 416±4.6 | 398±1.9 | 421±3.7 | 410±1.2 |
| t0.8r (ms) | 402±3.8 | 421±1.9 | 394±3.3 | 412±1.5 |
| +dF/dT (mN ms-1) | 1.51±0.7 | 1.66±0.2 | 1.50±0.5 | 1.56±0.1 |
| -dF/dT (mN ms-1) | 1.48±0.2 | 1.53±0.3 | 1.50±0.2 | 1.54±0.1 |
| Contractile variable . | Males (basal) . | Males (steroid-treated) . | Females (basal) . | Females (steroid-treated) . |
|---|---|---|---|---|
| F (mN) | 8.9±1.3 | 13.2±1.7 | 8.1±1.4 | 12.6±1.5 |
| tp (ms) | 416±4.6 | 398±1.9 | 421±3.7 | 410±1.2 |
| t0.8r (ms) | 402±3.8 | 421±1.9 | 394±3.3 | 412±1.5 |
| +dF/dT (mN ms-1) | 1.51±0.7 | 1.66±0.2 | 1.50±0.5 | 1.56±0.1 |
| -dF/dT (mN ms-1) | 1.48±0.2 | 1.53±0.3 | 1.50±0.2 | 1.54±0.1 |
Values are means ± s.e.m. (N=8). F,maximum twitch force; tp, time from stimulus to peak twitch force; t0.8r, time from peak twitch force to 80%relaxation.