人类鱼际肌的肌纤维型分布

Distribution of myofiber types in thenar muscles

关键词:  鱼际肌  肌纤维型  ATP酶

Key words:  fiber type distribution  thenar muscles  myofibriollar ATPase

摘要:

取5例(男4,女1),21～37岁,死亡后12h内的人体两侧手鱼际肌组织50块,用肌球蛋白ATP酶法,系统研究了各肌的肌纤维型分布.结果表明:人类鱼际肌中I型(慢缩)纤维的平均百分率在59%～67%之间,平均为62%显著高于上肢其它各肌群I型纤维的平均百分率(P＜0.05).鱼际肌的深、浅层间,多数肌I型纤维百分率接近.左、右侧别比较,除拇收肌横头右侧者显著高于左侧外,其余肌均未见显著的I型纤维侧别差异,结合肌电图和拇指功能,对这些差异的意义进行了分析讨论.

Abstract:

Samples of the human thenar muscles were taken from five healthy young cadavers (4 male, 1 female)died of accidents. The distribution and composition of type Ⅰand type Ⅱfibers in the thenar muscles were studied by histochemical method for myofibrillar ATPase.The results showed that the mean percentages of type Ⅰ fibers ranged from 59% to 67% in these thenar muscles and the total mean percentage was 62% The thenar muscles have significantly higher proportions of type Ⅰ fibers than those of the muscles in the arm and the forearm (P＜0.05). The proportion of type I fibers in the transterse head of the adductor pollic is was 67%, higher than that(59.6%) in the abductor pollicis breris (P＜0.01) There was no significant side difference between right and left side of the thenar muscles, except that in the transverse head of the adductor pollicis,which showed a higher proportions of type Ⅰ fibers in the right side.