MAMMALIAN MYOGENESIS SUBSEQUENT TO FETAL DENERVATION

胎儿去神经后的哺乳动物肌生成

• 批准号: 3326824
• 负责人: Marcia R. Ontell
• 金额: $ 14.93万
• 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/3326824
• 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.

在体内，肌肉发生与肌肉的发育同时发生