Use of dP/dt and rise time to estimate speed of shortening in muscle.
Use of dP/dt and rise time to estimate speed of shortening in muscle.
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使用 dP/dt 和上升时间来估计肌肉缩短的速度。
DOI：
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发表时间：
1985
影响因子：
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通讯作者：
J. Renaud
中科院分区：
文献类型：
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作者：
E. Stevens;J. Renaud
我们研究了无负荷时最大缩短速度(Vmax)与两个偶尔用来估计Vmax的变量之间的关系：等长强直收缩时的最大力变化率[(dp/dt)max]和等长强直收缩时达到最大力的一半的时间的倒数半上升时间(RHRT)。在两个实验中验证了这种关系：温度的影响和改变细胞外pH的影响，以检验(dp/dt)max或RHRT可以用来估计实验变量对Vmax的影响的大小的假设。在温度实验中，(dp/dt)max和RHRT均可用来估计Vmax的变化。(dp/dt)max明显高估了pH对Vmax的影响，但Vmax和RHRT的变化幅度无显著差异。我们的结果与其他人的结果一起表明，假设特定实验方案对Vmax的影响的大小一定可以通过测量(dp/dt)max或RHRT来预测是不合适的。
We examined the relationship between the maximum speed of shortening at zero load (Vmax) and two variables occasionally used to estimate Vmax: maximal rate of change of force during an isometric tetanic contraction [(dP/dt)max] and reciprocal of one-half rise time (RHRT), the time to achieve one-half the maximal force during an isometric tetanic contraction. The relationship was examined in two experiments on isolated toad sartorius muscle: the effect of temperature and the effect of changing pHe (extracellular pH) to test the hypotheses that (dP/dt)max or RHRT can be used to estimate the magnitude of the effect of experimental variables on Vmax. In the temperature experiment both (dP/dt)max and RHRT could be used to estimate changes in Vmax. The effect of pH on Vmax was markedly overestimated by (dP/dt)max, but there was no significant difference between the magnitude of the changes in Vmax and RHRT. Our results, taken with the results of others, suggest that it is inappropriate to assume that the magnitude of the effect of a particular experimental protocol on Vmax can necessarily be predicted by measuring (dP/dt)max or RHRT.