INTERACTIONA & RESPONSES TO STRESS IN VITRO

互动

• 批准号: 3158414
• 负责人: ALBERT J BANES
• 金额: $ 15.33万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-08-01 至 1993-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3158414
• 关键词: chickens; collagen; crosslink; exercise; fibroblasts; fluorescence microscopy; immobilization of body part; mechanical stress; protein biosynthesis; second messengers; sports injury; synovial fluid; tendon injury; tissue /cell culture; wound healing

Tendon injuries, particularly sports related injuries, constitute an increasing proportion of patients treated at our hospital, yet research in the cell biology of tendon healing is in its infancy. Of particular importance in tendon healing is the relationship of exercise and its underlying mechanism. The objective of this study is to explore possible mechanisms, responsible for the effects of mechanical simulation on tendon cell biologic (actin polymerization and cell migration) and biochemical responses (second messengers and matrix adaptations). Specific aims are: 1. to subject tendon and sheath cells to defined mechanical deformation regiments where the amplitude, duration, frequency and strain rates are known; 2. to investigate the mechanism by which mechanical activity is translated into a biochemical signal; 3. to understand how collagen metabolism is regulated in cells subjected to defined cyclic stretching in vitro. An instrument has been developed in my laboratory that will be used to apply regulated mechanical strain to collagen coated, flexible bottomed culture plates that support tendon cell adherence and growth. A mathematical expression relating a response of a cell to the mechanical factors, elongation, frequency and strain rate will be used to model experiments in culture that mimic physical activity experienced by tendon and sheath in vivo. Osteoblasts and endothelial cells are stimulated to divide by one regimen of cyclic strain whereas smooth muscle cells and pulp fibroblasts are retarded while tendon cells are refractory. Other responses such as alteration in protein synthesis and collagen metabolism specifically have been noted. An examination of key second messenger signalling pathways, such as, cAMP, PGE2, diacylglycerol and phosphoinositides will be performed using radioimmunoassay, chemical separation and protein kinase C measurements. Mitogenic responses of cells will be assayed by quantitation of DNA synthesis directly in stimulated cells and in conditioned medium. Collagen metabolism will be monitored by quantitation of mRNA, collagen synthesis, type an crosslink quality an quantity. Modelling the impact of physical deformation on tendon cells in culture may yield a quantitative solution to which exercise regimens work best in vivo to yield a healed tendon that is strong yet flexible.

肌腱受伤，尤其是与运动有关的伤害，构成了 在我们医院接受治疗的患者比例增加，但研究 肌腱愈合的细胞生物学仍处于起步阶段。 特别 在肌腱愈合中的重要性是运动的关系 基本机制。 这项研究的目的是探索可能 机制，负责机械模拟对肌腱的影响 细胞生物学（肌动蛋白聚合和细胞迁移）和生化 响应（第二使者和矩阵改编）。 具体目的是： 1。对肌腱和鞘细胞进行定义的机械变形 幅度，持续时间，频率和应变速率为 已知2。研究机械活动的机制 翻译成生化信号； 3。了解胶原蛋白 代谢受到经过定义的环状拉伸的细胞的调节 体外。 我的实验室已经开发了一种乐器 要在胶原蛋白涂层的胶原蛋白上施加调节的机械应变，柔性 支持肌腱细胞粘附和生长的培养板。 一个 数学表达与机械的响应有关 因素，伸长率，频率和应变率将用于建模 在培养中模仿肌腱体验的培养实验 和鞘在体内。 刺激成骨细胞和内皮细胞 除以一种环状菌株的一个方案，而平滑肌细胞和果肉 肌腱细胞难治性时，成纤维细胞会阻碍。 其他 诸如蛋白质合成和胶原蛋白代谢的改变等反应 特别是注意到了。 关键第二使者的检查 信号通路，例如CAMP，PGE2，二酰基甘油和 磷酸肌醇将使用放射免疫测定法进行化学 分离和蛋白激酶C测量。 细胞的有丝分裂反应 将通过直接在刺激中定量DNA合成来测定 细胞和条件培养基。 胶原代谢将由 mRNA的定量，胶原蛋白合成，类型A的交联质量A 数量。 建模物理变形对肌腱细胞中细胞的影响 培养可能会产生一种锻炼方案的定量解决方案 最好的体内体内产生强壮但灵活的愈合肌腱。