Ohno T
Japan
Research Article
Effect of Inorganic Phosphate and Low pH on the Force-Velocity Relation
of Single Skinned Skeletal Muscle Fibers Studied by Applying Parabolic
Fiber Length Changes
Author(s): Ohno T, Arao T, Chaen S and Haruo SugiOhno T, Arao T, Chaen S and Haruo Sugi
Although force-velocity (P-V) relation is important to obtain insights into kinetics of actin-myosin interaction in muscle, determination of P-V relation in skinned muscle fibers are difficult mainly due to gradual deterioration at the two cut fiber ends, which makes it impossible to obtain enough data points to construct P-V curve over the whole range of forces. In addition, determination of the maximum shortening velocity Vmax by back extrapolation of limited data points to velocity axis is ambiguous because of the steep force versus velocity relation. To overcome these difficulties, we developed a novel method to obtain continuous P-V curves over the whole range of forces from 0 to the maximum isometric force Po, by applying length changes, with time course L=-kt2, to Ca2+-activated skinned fibers, so that time derivative of length change, i.e. shortening velocity V=-dL/dt=-2kt; na.. View More»
DOI:
10.4172/2157-7439.1000428