应用dF/dt_(max)指标测定骨骼肌收缩能力

APPLICATION dF/dt_(max) INDEX FOR DETERMINATIONS OF SKELETAL CONTRACTILITY

目的 :探讨张力上升最大速率 ( +dF/dtmax)与张力下降最大速率 ( -dF/dtmax)作为反映骨骼肌收缩能力方面的较灵敏指标。方法 :采用不同游泳运动的小白鼠模型 ,记录腓肠肌收缩的最大张力 (Fmax) ,+dF/dtmax与 -dF/dtmax,观察腓肠肌超微结构的变化。结果 :一般运动负荷组线粒体数量增加 ,肌丝排列整齐 ,腓肠肌Fmax,-dF/dtmax比对照组明显增加 (P <0 .0 5) ,+dF/dtmax坛加非常显著 (P <0 .0 1)。过度运动负荷组线粒体稀疏 ,肌丝排列较乱 ,腓肠肌Fmax、-dF/dtmax比对照组明显减小 (P <0 .0 5) ,+dF/dtmax 减小非常显著 (P <0 .0 1)。结论

Aim: To analyze the most force rising ratio (+dF/dt max ) and t he most force descending ratio (-dF/dt max ) for more sensitive index of s keletal contractility. Methods: Mouse model of swimming trainin g was used, most force (f max ) , +dF/dt max and -dF/dt max of gas trocnemius contracting were measured and changes of gastrocnemius supermicro-s t ructure was observed. Results: Mitochondria increased and myonem e was regular in general training load, gastrocnemius F max . -dF/dt max significantly increased than in control (P<0.05), +dF/dt max increas ed more significantly (P<0.01). Mitochondria was rare and myoneme was unusua l in overtraining load, gastrocnemius F max 、-dF/dt max reduced signif icantly than in control (P<0.05), +dF/dt max reduced more significantly (P<0.01). Conclusion: +dF/dt max is better index than F max in judging skeletal contractivity.