Differential effects of sinusoidal vibrations on tension and stiffness in Mytilus smooth muscle during catch state.

Sinusoidal vibrations (10-100 Hz, 0.5-2.5%) reduced catch tension in the anterior byssal retractor muscle of Mytilus edulis, while the stiffness measured as the tension increment in response to the stretch phase of vibration did not change appreciably, indicating that the vibration-induced reduction of catch tension may not be simply explained as being due to the detachment of cross-links between actin and myosin.