| Volitional movement requires the co-ordinated function of muscle tendon and bone. In the musculoskeletal system, muscles generate force and transmit that force via tendons to bone. Tendon along with other connective tissue is an integral component of the force transmission system, The effects of exercise on muscle and bone tissue are well documented. However, relatively few studies have been published on the adaptation of tendon to exercise. Understanding ofthe response of the musculoskeletal system to exercise is incomplete without further informationon about tendon adaptation. The response of tendon to exercise may be measured at the structural, mechanical and biochemical levels; however, most studies have been limited to measuring only one or two variables, few studies have integrated structural, biomechanical and biochemical parameters. The difference in research object, the different localization of the tendons being studied as well as the training way inthe past experiments causes the research conclusion to be inconsistent. All of these makes it difficult to get to the bottom of the rules lie in the tendon remolding process under exercise.The growth factors were considered concerned the cell signal conduction introduced by machinery load. Many experiments discovered that the machinery load may cause many kinds of growth factors' expression to increase. The majority of these experiments involved the raised cell in vitro. Few experiments have dealed with the expression of TGF- β1 in health tendon under long-term exercise training. In studies of recent years, it was founded that TGF-beta 1 can stimulates the tendon cell multiplication and the tendon matrix synthesis, TGF-β1 act as the vital role in the process of growth and repair in tendons. Most of the present studies on the function of TGF-β1 concentrates on the process of repair after the tendon damage, little has pay attention to the role of TGF-β1 in the remolding process taken place in the health tendon under stress.This experiment investigated the structural and biomechanical changes of rats, Achilles tendons in the remolding process under different endurance training patterns. Further experiment studied the changes of biochemical ingredients and the effects of TGF- beta 1 in the process of tendon remolding under the intensified cyclic training pattern.8-weeks old male Wistar rats were used as research objects in this two-stage animal experiment. In the firststage, moderate training, Strengthened training and intensified cyclic training were carried on separately between different groups of rats. Results showed that the changes of biomechanical properities were identical to the changes of tissue structure. Training had no influence on the cross sectional area. After 8 weeks of intensified cyclic training, the mechanical properities of rat Achilles tendons were significently higher than that of the untrained groups. Intensified Cyclic training can accelerate the reraodling process .The further experiment measured the content of collagen through the test of hydroxyproline concentration and evaluted the expression of TGF- β1 and collagen III in rats' Achilles tendons under intensified cyclic training by the application of immunohistochemical dyeing and semi-quantitive analysis method. Results showed that, in the early stage of training, collagen III expression strengthens and weakens gradually along with training time lengthening. In the training process, the tendon collagen content had not changed. The TGF-β1 expression changed consistently with the dynamic changes of the activity of tendon cells, which was observed under electron microscope in the first stage experiment.Through this research, we concluded that, during the process of tendon remolding under exercise introduced stress, collagen synthesis and degeneration coexisten in an equilibrium phase. The increase of collagen III in the early stage of training suggests the acceleration of collagen metabolism activity,which accelerates the remodeling of...
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