CONNECTIVE TISSUE CHANGES IN OVER USED SKELETAL MUSCLE

过度使用的骨骼肌中结缔组织的变化

• 批准号: 3734305
• 负责人: GERARD C GORNIAK
• 金额: --
• 依托单位: FLORIDA AGRICULTURAL AND MECHANICAL UNIV
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3734305
• 关键词: animal age group; connective tissue; fatigue; hamsters; histology; image processing; muscle stress; muscle tension; neuromuscular disorder; pathology; striated muscles; tensile strength

The active contractile components of skeletal muscle have and continue to be studied extensively. In contrast, passive connective tissue components have been neglected. This neglect is puzzling as disorders such as muscular dystrophy, myositis, ischemic muscular necrosis and others are associated with intramuscular connective tissue changes. Further, neural and vascular channels to the active components pass within the surrounding and very plastic connective tissue network. the aims of this project are 1) to determine the changes in the quantity and composition of intramuscular connective tissue when muscles are stressed by over-use; 2) to correlate the changes in muscular connective tissue with twitch tension, tetanic tension and fatigability; 3) to determine if changes are age and load dependent; and 4) to establish a baseline for future studies involving pathological neuromuscular disorders. Juvenile (3-4 weeks) and adult (12-13 weeks) syrian hamsters will be subdivided randomly into a control group and two experimental groups. In experimental group I, muscle over-use will be accomplished by unilateral detachment of a synergist muscle in the leg. In experimental group II, muscle over-use in the leg muscles will be accomplished by applying subcutaneous loads in the lumbosacral region that are carried by the animals for 6 weeks. For all groups, (1) the percent composition of collagen, elastic and reticular fibers will be determined by serial histological procedures; (2) the quantity of connective tissue will be measured using computer digitizing techniques and (3) the physiological properties of the muscles determined and correlated with morphological changes. It is hypothesized that (1) tensile stresses in over-used muscles increase the quantity of intramuscular collagen, but not elastin or reticulin, increasing muscle stiffness but not maximum tetanic tension, (2) increased stiffness produces increased fatigability due to capillary compression, and (3) the magnitude of connective tissue changes are age dependent.

骨骼肌的主动收缩成分具有并继续 被广泛研究。 相反，被动结缔组织 组件已被忽略。 这种忽视令人困惑，因为疾病 例如肌肉营养不良，肌炎，缺血性肌肉坏死和 其他与肌内结缔组织变化有关。 此外，活动成分的神经和血管通道通过 在周围和非常塑料结缔组织网络中。 这 该项目的目的是1）确定数量的变化和 当肌肉应力时肌内结缔组织的组成 通过过度使用； 2）将肌肉结缔组织的变化相关联 带有抽搐的张力，tetanic张力和疲劳性； 3）确定 如果变化是年龄和负载依赖性的； 4）建立一个基准 未来涉及病理神经肌肉疾病的研究。 少年 （3-4周）和成人（12-13周）叙利亚仓鼠将被细分 随机分为对照组和两个实验组。 在 实验组I，肌肉过度使用将通过单侧完成 腿部协同肌肉的分离。 在实验组II中 肌肉过度使用腿部肌肉将通过涂抹来完成 在腰s骨区域的皮下负荷。 动物持续6周。 对于所有组，（1） 胶原蛋白，弹性和网状纤维将由串行确定 组织学程序； （2）结缔组织的数量将是 使用计算机数字化技术测量，（3）生理 确定并与形态学相关的肌肉的特性 更改。 假设（1）过度使用的拉伸应力 肌肉增加肌内胶原蛋白的数量，但不增加弹性蛋白 或网状蛋白，增加肌肉刚度，但不会最大 张力，（2）增加刚度会导致增加的疲劳性 毛细管压缩，（3）结缔组织的大小变化 是依赖年龄的。