INFLUOF PASSIVE EXERCISE ON STRETCH REFLEX PROPERTIES IN RATS W/SC INJURY

这个子项目是许多利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 痉挛是一种对肌肉拉伸的异常反射反应，通常导致脊髓损伤（SCI）后的损伤。 脊髓损伤引起的脊髓上控制的丧失导致了这种反射亢进的发展，但确切的机制尚未阐明。 需要深入了解痉挛的机制和开发更有效的治疗方法来改善SCI患者的功能和生活质量。 本研究提出了一种新的模型，用于直接测量在脊髓横断大鼠小腿肌肉的强制拉伸过程中的肌电图（EMG）和关节扭矩。 本研究的目的是检查被动运动对痉挛的影响，并确定受伤后痉挛的出现。 虽然幅度较小，但伸展反射存在于脊柱完整的人类和大鼠中。 相比之下，正常人没有一种运动现象，称为牵张反射的终结。 这项研究将提出SCI大鼠牵张反射卷紧的第一个证据，卷紧行为将作为一种手段来量化痉挛，并进行组间和纵向比较，这是不可能通过标准EMG测量。 拟定研究旨在比较横断对照组和接受8周每日被动运动的横断组。 痉挛测试将涉及2个单独的方案。 速度协议将使用3种不同的拉伸速度来记录损伤后拉伸反射的出现。 发条协议将使用3种不同的频率来测量反射亢进的量。 这两种方案将每周进行一次测试。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Spasticity is an abnormal reflex response to muscle stretch that commonly results in impairment following spinal cord injury (SCI). The loss of supraspinal control due to SCI contributes to the development of this hyperreflexia, but the exact mechanisms have not been elucidated. Insight into the mechanisms of spasticity and the development of more effective treatments are needed to improve the function and quality of life in individuals with SCI. This study proposes a new model for the direct measure of the electromyography (EMG) and joint torque during the imposed stretch of the calf muscles in spinal cord transected rats. The aims of the study are to examine the effects of passive exercise on spasticity and to determine the emergence of spasticity post injury. Although smaller in magnitude, stretch reflexes are present in spinal intact humans and rats. In contrast, normal humans do not have a motor phenomenon called windup of the stretch reflex. This study would present the first evidence of stretch reflex windup in a SCI rat, and the windup behavior will serve as a means to quantify spasticity and make inter-group and longitudinal comparisons that are not possible by standard EMG measurement. The proposed study is designed to allow comparison of a transected control group and a transected group receiving daily passive exercise over an 8 week period. Tests of spasticity will involve 2 separate protocols. The velocity protocol will use 3 different velocities of stretch to document the emergence of stretch reflexes post injury. The windup protocol will use 3 different frequencies to measure the amount of hyperreflexia. Both protocols will be tested on a weekly basis.