Table 2.

Isometric mechanical properties of fibre bundle preparations of transverse muscle mass of tentacle and arm of Loligo pealei

TentacleArm
P0 (mN mm-2)130.9±55.6 (12)468.3±91.2 (5)
Ptw/P00.66±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).