强化循环训练促进跟腱组织塑形改建的实验研究

目的考察耐力运动训练过程中大鼠跟腱组织结构与生化成分的变化及不同训练模式与大鼠跟腱塑形改建规律的对应关系。方法120只8周龄雄性Wistar大鼠按训练方式、训练时间两因素析因设计以体重区组进行随机分组，训练方式有自由活动、中等负荷训练、强化训练、强化循环训练4个水平，训练时间有1、2、3、4、6、8周6个水平，共24组，每组5只。训练结束后切取跟腱组织，通过扫描电镜及透射电镜观察其超微结构，并应用碱解法测定强化循环训练组大鼠跟腱中羟脯氨酸的含量，以其代表胶原蛋白总量的变化；通过免疫组织化学染色的方法对该训练组大鼠跟腱组织中Ⅲ型胶原蛋白含量的动态变化进行半定量分析。结果在训练过程中，跟腱的组织结构出现由以损伤为主到修复重建占主导的动态变化，循环训练模式下损伤表现出现早，程度轻，持续时间最短。跟腱胶原蛋白总量在训练过程中保持不变，而Ⅲ型胶原的表达呈现训练早期增强，随塑形改建的进行又逐渐减弱的规律。在运动训练下肌腱组织的塑形改建过程中，胶原的新生与破坏，合成与降解是相平衡的过程。训练早期Ⅲ型胶原的含量增加提示应力作用下胶原代谢活动加速，促进组织结构发生改建。结论肌腱在运动训练中的塑形改建是通过其内部结构的重塑而非组织肥大来完成的。训练中负荷重复的次数较之单次负荷的大小对肌腱的塑形改建更具积极意义，强化循环训练可以加速跟腱的塑形改建。

Experimental studies on the effects of strengthened training on remodeling of Achilles tendon of rats

Objective To investigate the structural and biomeehanical changes in rats, Achilles tendon during a period of physical training, and the relationship between the training mode and the modeling of Achilles tendon in rats. Methods 120 male Wistar rats, 8 weeks in age, were randomized by body weight design into 24 groups with 5 rats for each group according to different training mode and time of training. The 4 modes of training were the free activity, training, with moderate load of performance, intensified training and cyclic intensified training. The duration of training varied from 1, 2, 3, 4, 6 to 8 weeks. After training, the Achilles tendons were harvested for examinations. The ultrastructural changes in Achilles tendons were observed both by scanning and transmission electron microscope. For the cyclic intensified training group, the content of hydroxyproline in the Achilles tendons, which was taken as the amount of total colla- gen, was measured by alkaline hydrolysis, and immunohistochemistry staining was employed to analyze semi-quantitatively the dynamic changes in collagen III expression. Results The dynamic changes in the Achilles tendon from structural injury to repair and reconstraction could be observed at the same period of training process. In the cyclic intensified training group injury to the Achilles tendon occurred in a mild grade early and lasted for a short period. The total collagen nuaintained in a content level during the process of training, while the ex- pression of collagen III increased during the early stage of training, then declined gradually accompanying with remodeling. Conclusion During the process of training the tendon remodeling was accomplished by reconstruction of internal structures rather than proliferation of tissue. The number of repeated burdening may be more important than the quantity of burden in the process of tendon remodeling. The cyclic intensified training may accelerate the process of tendon remodeling.