Seow C Y, Stephens N L
Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
J Appl Physiol (1985). 1988 May;64(5):2053-7. doi: 10.1152/jappl.1988.64.5.2053.
Zero-load velocity (V0) as a function of the length of canine tracheal smooth muscle was obtained by applying zero-load clamps to isotonically contracting muscle under various loads. The load clamps were applied at a specific time after onset of contraction. The magnitude of the isotonic load therefore determines the length of the muscle at the moment of release or at the moment the unloaded shortening velocity was measured. A family of such V0-muscle length (L) curves was obtained at 1-s intervals in the time course of contraction. The V0-L curve was fitted by a parabolic function with satisfactory goodness of fit. The maximum shortening velocity at optimum muscle length varied with time, but the minimum length at which V0 diminished to zero was time independent.
通过在不同负荷下对等张收缩的肌肉施加零负荷夹，获得犬气管平滑肌长度的函数零负荷速度（V0）。负荷夹在收缩开始后的特定时间施加。因此，等张负荷的大小决定了释放时刻或测量无负荷缩短速度时刻的肌肉长度。在收缩过程中，以1秒的间隔获得了一系列这样的V0-肌肉长度（L）曲线。V0-L曲线用抛物线函数拟合，拟合优度令人满意。最佳肌肉长度下的最大缩短速度随时间变化，但V0降至零的最小长度与时间无关。
