Force-velocity properties of human skeletal muscle fibres: Myosin heavy chain isoform and temperature dependence
Force-velocity properties of human skeletal muscle fibres: Myosin heavy chain isoform and temperature dependence
复制标题
DOI：
10.1113/jphysiol.1996.sp021617
复制
发表时间：
1996-09-01
影响因子：
5.5
通讯作者：
Reggiani, C
中科院分区：
文献类型：
--
作者：
Bottinelli, R;Canepari, M;Reggiani, C
1. 对大量（n = 151）人类皮肤骨骼肌纤维进行了研究。通过在 12 摄氏度下进行负载钳操作获得了 67 根纤维的力-速度曲线。在每根纤维中，最大缩短速度 (V-max)、最大功率输出 (W-max)、最佳速度（产生 W-max 的速度，V-opt）、最佳力（产生 W-max 的力，P-opt）、比张力（P-o/CSA， 评估等长张力/横截面积）。还通过松弛测试程序在 12 OC 下测定了不同组 (n = 57) 纤维的空载缩短速度 (V-o)。2．所有用于力学实验的纤维均根据十二烷基硫酸钠（SDS）-聚丙烯酰胺凝胶电泳的肌球蛋白重链（MHC）异构体组成进行表征，分为五种类型：I型（或慢速）、IIA和IIB型（或快速）、I-IIA和IIA-IIB型（或混合型）。 3．发现 V-max、W-max、V-opt、P-opt、V-opt/V-max 比率、P-o/CSA 和 V-o 取决于 MHC 同工型组成。 I 型纤维的所有参数均显着低于快纤维（IIA 型和 IIB 型）。在快纤维中，II A 型纤维中的 V-max、W-max、V-opt 和 V-o 显着低于 IIB 纤维，而 P-opt、P-o/CSA 和 V-opt/V-max 相似。4．在 12-22 摄氏度范围内的一组 21 根光纤中评估了 V-o 和 P-o/CSA 的温度依赖性。还研究了一组 6 根光纤中的 V-max 的温度依赖性。根据阿伦尼乌斯图计算的最大缩短速度的 Q(10) (5.88) 和活化能 E (125 kJ mol(-1)) 值表明其具有非常高的温度敏感性。 P-o/CSA 在 12-17 摄氏度范围内对温度的依赖性很强，但在 17 至 22 摄氏度之间依赖性较小。
1. A large population (n = 151) of human skinned skeletal muscle fibres has been studied. Force-velocity curves of sixty-seven fibres were obtained by load-clamp manoeuvres at 12 degrees C. In each fibre maximum shortening velocity (V-max), maximum power output (W-max), optimal velocity (velocity at which W-max is developed, V-opt), optimal force (force at which W-max is developed, P-opt), specific tension (P-o/CSA, isometric tension/cross-sectional area) were assessed. Unloaded shortening velocity (V-o) was also determined at 12 OC in a different group (n = 57) of fibres by slack-test procedure.2. All fibres used for mechanical experiments were characterized on the basis of the myosin heavy chain (MHC) isoform composition by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis and divided into five types: type I (or slow), types IIA and IIB (or fast), and types I-IIA and IIA-IIB (or mixed types).3. V-max, W-max V-opt, P-opt, V-opt/V-max ratio, P-o/CSA and V-o were found to depend on MHC isoform composition. All parameters were significantly lower in type I than in the fast (type IIA and IIB) fibres. Among fast fibres, V-max, W-max, V-opt and V-o were significantly lower in type II A than in IIB fibres, whereas P-opt, P-o/CSA and V-opt/V-max were similar.4. The temperature dependence of V-o and P-o/CSA was assessed in a group of twenty-one fibres in the range 12-22 degrees C. In a set of six fibres temperature dependence of V-max was also studied. The Q(10) (5.88) and activation energy E (125 kJ mol(-1)) values for maximum shortening velocity calculated from Arrhenius plots pointed to a very high temperature sensitivity. P-o/CSA was very temperature dependent in the 12-17 degrees C range, but less dependent between 17 and 22 degrees C.