Mashima H, Okada T, Okuyama H
Jpn J Physiol. 1979;29(1):85-98. doi: 10.2170/jjphysiol.29.85.
Tension-length, load-velocity and tension-extension relations were studied in the taenia coli muscle of the guinea pig weighing 0.25--0.5 kg at 36--37 degrees C. The muscle was relaxed by 10(-6) g/ml adrenaline and stimulated by a strong AC field. The tension-length diagram was far wider than that of the skeletal muscle and sufficient tension was generated at longer lengths than 1.8 Lm, where Lm is the optimal length at which the maximum tension, Fm, is generated. The developed force per unit cross-sectional area was almost unchanged between 1.2--2.0 Lm. Average of the maximum forces was 2.2 kg/cm2. Load-velocity curves obtained at various isometric forces at Lm coincided with each other, if the velocity was plotted against the relative force. All curves can be expressed by a single force-load-velocity equation, (P+A)(v+b)=b(F+A), A=(F/Fm)a, where P is the load, F the isometric force, v the velocity, a and b are constants. The maximum velocity per unit muscle length was constant, irrespective of the muscle length. The compliance of the series elastic component, that is, the slope of the tension-extension curve, did not depend on the isometric force but decreased with decreasing muscle length. The internal lengthening of the series elastic component by the full isometric tension was about 3% of the muscle length at Lm.
在36 - 37摄氏度下，对体重0.25 - 0.5千克的豚鼠结肠带肌肉进行了张力 - 长度、负荷 - 速度和张力 - 伸长关系的研究。肌肉用10(-6)克/毫升肾上腺素松弛，并由强交流电场刺激。张力 - 长度图比骨骼肌的宽得多，并且在大于1.8Lm的长度下产生了足够的张力，其中Lm是产生最大张力Fm的最佳长度。在1.2 - 2.0Lm之间，单位横截面积产生的力几乎不变。最大力的平均值为2.2千克/平方厘米。如果将速度与相对力作图，在Lm处各种等长力下获得的负荷 - 速度曲线相互重合。所有曲线都可以用一个单一的力 - 负荷 - 速度方程表示：(P + A)(v + b) = b(F + A)，A = (F/Fm)a，其中P是负荷，F是等长力，v是速度，a和b是常数。单位肌肉长度的最大速度是恒定的，与肌肉长度无关。串联弹性成分的顺应性，即张力 - 伸长曲线的斜率，不取决于等长力，而是随着肌肉长度的减小而减小。在完全等长张力下，串联弹性成分的内部伸长约为Lm处肌肉长度的3%。
