摘要
目的研究分析了成年SD大鼠外侧腓肠肌各肌亚体内肌纤维的分布与肌球蛋白重链异构体(MHCs)的构成。方法应用琥珀酸脱氢酶(SDH)组织化学染色分析其4型肌纤维构成比例与横切面积,并以十二烷基硫酸钠-聚丙烯酰胺小孔梯度凝胶电泳(SDS-PAGE)检测肌球蛋白重链异构体。结果Ⅰ型慢缩氧化(SO型)肌纤维、ⅡX型快缩氧化(FO型)肌纤维、ⅡA型快缩氧化酵解(FOG型)肌纤维及ⅡB型快缩酵解(FG型)肌纤维的构成比例在内侧亚体分别为(10.2±4.1)%(、2.8±2.1)%、(25.7±9.6)%、(61.3±10.1)%;在外侧浅亚体分别为(15.9±8.2)%、(6.1±2.6)%(、22.8±11.5)%(、55.2±12.6)%;而在外侧深亚体则分别为(21.3±9.2)%、(9.8±2.5)%、(18.5±8.7)%(、50.4±10.9)%。4型肌纤维均呈交错式镶嵌型分布。Ⅰ型肌纤维横切面积较小,ⅡX型肌纤维横切面积最小,ⅡA型肌纤维横切面积中等,ⅡB型肌纤维横切面积最大。与使用SDS-PAGE在内侧亚体、外侧浅亚体及外侧深亚体分别发现的肌球蛋白重链异构体(MHCs)所确定的MHCsⅠ、MHCsⅡx(或Ⅱd)、MHCsⅡa、MHCsⅡb相对应。结论大鼠外侧腓肠肌的重要功能是屈膝关节和伸跗关节,在提踵推进躯体向前和需少量肌力活动时,主要依靠外侧浅、深亚体的肌纤维完成。只有快速运动使肌力需要25%以上时,才有内侧亚体的参与。
Objective To analyse and study the distribution of muscle fiber and the composition of myosin heavy chain isoforms（MHCs） in each muscular subvolume of the lateral gastrocnemius of adult SD rats. Methods Succinate dehydrogenase （SDH） staining was applied to analyse the proportions of muscle fibers of four types and sodium dodecyl sulphate-polyacrylamide gel electrophoresis（SDS-PAGE） was also used to measure myosin heavy chain isoforms（MHCs）. Results The proportions of types Ⅰ （SO）, Ⅱ X（FO）, ⅡA（FOG） and Ⅱ B（FG） muscle fibers in medial subvolume were （10.2±4.1）% ,（2.8±2.1）%, （25.7 ± 9.6） % ,（61.3 ± 10.1） % respectively, （ 15.9 ± 8.2） % ,（6.1± 2.6） % ,（22.8 ± 11.5） % ,（55.2 ± 12.6） % in lateral superficial subvolume, （21.3 ±9.2） % ,（9.8 ± 2.5） % ,（18.5 ± 8.7） %, （50.4 ± 10.9） % in lateral profound subvolume. The distribution of muscle fibers of four types was of a crisscross and mosaic pattern. Type Ⅱ X muscle fiber had the smallest transverse area and type ⅡB the biggest, with a medium and a smaller transverse areas for types Ⅱ A and Ⅰ respectively. They were conformed to MHCs Ⅰ , MHCs Ⅱ X, MHCs Ⅱ a, MHCs Ⅱb that were separately found in medial subvolume, lateral superficial subvolume and lateral profound subvolume with SDS-PAGE. Conclusion The important function of rat lateral gastrocnemius was flexion of knee joint and extension of ankle joint. The lateral superficial subvolume and the lateral profound subvolume seem to take more part in elevating the calcanens and small muscular movements, and the medial subvolume plays a role in fast movements when muscular power is needed to a degree greater than 25 %.
出处
《解剖学报》
CAS
CSCD
北大核心
2007年第1期93-97,共5页
Acta Anatomica Sinica
基金
江苏省教育厅自然科学基金资助项目(03KJD180175)
南通大学自然科学基金资助项目(05ZO28)
