Isometric mechanical properties of fibre bundle preparations of transverse muscle mass of tentacle and arm of Loligo pealei
Tentacle | Arm | |
---|---|---|
P0 (mN mm-2) | 130.9±55.6 (12) | 468.3±91.2 (5) |
Ptw/P0 | 0.66±0.06 (10) | 0.03±0.02 (10) |
TPT (ms) | 33.6±3.0 (28) | 59.6±10.2 (17) |
RT50 (ms) | 52.7±7.3 (28) | 153.4±65.9 (17) |
Values are means±S.D. (N).
P0 is the peak force in a brief tetanus (0.2 s stimulation at 80 Hz for the tentacle and 160 Hz for the arm, the stimulus frequencies that showed the highest force for each type); Ptw/P0 is the twitch:tetanus force ratio; TPT is the time from onset of stimulation to development of maximum force during a twitch; RT50 is half-relaxation time from maximum force during a twitch.
Note that P0 is biased low, especially for the arm preparations (see Discussion).