MAMMALIAN MYOGENESIS SUBSEQUENT TO FETAL DENERVATION

胎儿去神经后的哺乳动物肌生成

• 批准号: 3326828
• 负责人: Marcia R. Ontell
• 金额: $ 12.23万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-03-01 至 1993-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3326828
• 关键词: axon; biological polymorphism; cell death; denervation; densitometry; developmental neurobiology; electrofocusing; electron microscopy; embryo /fetus cell /tissue; gel electrophoresis; histogenesis; immunocytochemistry; innervation; laboratory mouse; lasers; motor neurons; myogenesis; neural plate /tube; newborn animals; phase contrast microscopy; spinal cord; striated muscles

In vivo myogenesis occurs simultaneously with the development and maturation of the fetal nervous system. Because the mammalian fetus has not been easily manipulated, much of what we know about nerve-muscle relationships during development has been gained from studies of developing chick. Recent studies suggest that nerve-muscle relationships in mammalian fetuses may differ from those in chick. A new technique which permits laser ablation of the lumbosacral region of the fetal, murine spinal cord, without interfering with fetal viability and further maturation, will allow us to determine the effect of fetal denervation on myotube formation, myotube survival and on the generation of myotube diversity in mammalian muscles. Evaluations will be made with electron microscopy, quantitative morphometry, gel electrophoresis and immunocytochemistry. These studies will provide information concerning alterations in genetically determined patterns of myogenesis by an environmental factor (i.e., the developing motoneuron). Little is known about the effects of axotomy, performed at various fetal stages, on the survival of mammalian motoneurons. Techniques which permit transection of the ventral roots of spinal nerves or of the sciatic nerve will allow determination of whether mammalian axons can survive axotomy and whether (and under what conditions) they can innervate striated muscle. If axotomized motoneurons survive, the effect of delayed innervation and/or transient fetal denervation on muscle development will be assessed. If they fail to survive, alterations in the size and location of motoneuron pools to adult muscles subjected to partial denervation during fetal development will be determined. Evaluations will be made with electron microscopy, physiology and by examining the spinal cords of mice whose muscles were injected with HRP. The proposed studies are relevant to human development.

体内肌生成与发育同时发生 胎儿神经系统的成熟。因为哺乳动物的胎儿还没有 很容易被操纵，我们所知道的关于神经肌肉的大部分知识 发展过程中的关系是从发展研究中获得的 小鸡。最近的研究表明，哺乳动物的神经肌肉关系 胎儿可能与小鸡有所不同。允许激光的新技术 胎儿腰骶部、小鼠脊髓的消融， 在不干扰胎儿活力和进一步成熟的情况下，将允许 我们确定胎儿去神经对肌管形成的影响， 哺乳动物肌管存活和肌管多样性的产生 肌肉。评估将通过电子显微镜、定量 形态测定法、凝胶电泳和免疫细胞化学。这些研究 将提供有关基因决定的改变的信息 环境因素（即发育中的肌细胞）影响的肌生成模式 运动神经元）。人们对轴索切断术的影响知之甚少，该手术在 各个胎儿阶段对哺乳动物运动神经元存活的影响。技巧 允许横断脊神经或神经的腹侧根 坐骨神经将有助于确定哺乳动物的轴突是否可以 轴索切除术中能否存活以及它们是否（以及在什么条件下）可以神经支配 横纹肌。如果轴突运动神经元存活，延迟的影响 神经支配和/或短暂的胎儿去神经支配对肌肉发育的影响 进行评估。如果它们无法生存，则需要改变大小和位置 运动神经元池到接受部分去神经支配的成人肌肉 是在胎儿发育过程中确定的。评估将通过 电子显微镜、生理学和检查小鼠脊髓 他们的肌肉注射了 HRP。拟议的研究涉及 人类发展。