MUSCLE REGENERATION AND AGING

本计划项目的总体目标是检验以下假设： 去神经支配的变化是造成肌肉中大部分缺陷的原因。 在老年时期看到的质量和功能， 失神经肌肉的生物学，能够设计出方法， 成功地防止或逆转去神经萎缩的过程。 项目1将主要采用形态学方法来研究 卫星细胞生物学和组织切片定位都很重要 分子在肌肉在不同阶段的老化和去神经， 以及评估失神经和/或老化的恢复的成功性 肌肉移植或电刺激。 在小组目标1和2中， P-1将提供关于下列人员的人数和分布情况的定量数据： 年轻和老年大鼠失神经肌肉纤维上的卫星细胞，如 以及通过免疫细胞化学方法定位 生肌调节因子家族和蛋白质EF-1 α和S1。 此外，P-1将从形态学上评估移植物的成功率， 去神经和老化的肌肉移植到年轻的宿主大鼠体内。 在目标3组中， p-1将使用卫星细胞分析和分子定位技术 为了验证电刺激失神经肌肉 显著降低失神经萎缩的速率和程度。 P-1 还将评估移植物的形态刺激去神经 肌肉在测试的假设，刺激去神经移植 肌肉恢复比非刺激失神经移植更好 肌肉. 对于第4组目标，P-1将评估移植物的形态 已经用快神经或慢神经重新支配的肌肉， 年轻、成年、老年和极老年大鼠。 这些研究预计 为了阐明失神经萎缩的细胞基础， 不同时期的失神经支配后的恢复模式， 肌肉. 这些数据将用于分析结构和 老化肌肉的功能缺陷。

The overall aims of this Program Project are to test the hypothesis that denervation changes are responsible for much of the deficit in muscle mass and function that is seen in old age and to discover enough about the biology of denervated muscle to be able to devise methods for successfully preventing or reversing the course of denervation atrophy. Project 1 will employ principally morphological methods to investigate both satellite cell biology and to localize in tissue sections important molecules in muscles at various stages of aging and denervation, as well as to asses the success of restoration of denervated and/or aging muscle by grafting or electrical stimulation. In Group Aims 1 and 2, P-1 will provide quantitative data on the numbers and distribution of satellite cells on denervated muscle fibers of young and old rats, as well as localizing by immunocytochemical means molecules of the myogenic regulatory factor family and the proteins EF-1alpha and S1. In addition, P-1 will assess morphologically the success of grafts of denervated and aged muscles into young host rats. In Group Aim 3, p-1 will use satellite cell analysis and molecular localization techniques to test the hypothesis that electrical stimulation of denervated muscle significantly reduces the rate and degree of denervation atrophy. P-1 will also assess the morphology of grafts of stimulated-denervated muscles in testing the hypothesis that grafts of stimulated-denervated muscles recover better than grafts of non-stimulated denervated muscles. For Group aim 4, P-1 will assess the morphology of grafts of muscles that have been reinnervated with either fast or slow nerves in young, adult, old and extremely old rats. These studies are expected to clarify the cellular basis underlying denervation atrophy and the patterns of recovery seen after different periods of denervation of muscle. These data will than be used in the analysis of structural and functional deficits in aging muscle.