权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Ankle dorsiflexion splinting enhances endothelial function of aged leg muscles

踝关节背屈夹板增强老年腿部肌肉的内皮功能

基本信息

批准号：
8644007
负责人：
Demetra Christou
金额：
$ 21.9万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-30 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8644007
关键词：
Activities of Daily Living Acute Aerobic Aerobic Exercise Age Aging Ankle Applications Grants Arterial Occlusive Diseases Arteries Articular Range of Motion Blood Vessels Blood flow Clinical Clinical Research Clinical Trials Complex Data Elderly Endothelium Excision Exercise Florida Foot-drop Functional disorder Funding Future Goals Hindlimb Home environment Human Immobilization Inbred F344 Rats Individual Intervention Investigation Joints Leg Length Measures Modality Modeling Muscle Muscle function Muscular Atrophy Nature Patients Performance Peripheral Peripheral arterial disease Physical Function Physical activity Play Population Rattus Regulation Resistance Rest Skeletal Muscle Soleus Muscle Splint Device Stretching Structure of popliteal artery Surgeon Testing Training Training Programs Translating United States National Institutes of Health Universities Vasodilation Walking Work aged base clinical practice clinically significant combat design flexibility high risk human subject improved in vivo muscle aging novel strategies older patient post stroke preclinical study prevent professor programs public health relevance research study sedentary

项目摘要

DESCRIPTION (provided by applicant): Endothelial function of the skeletal muscle resistance vasculature declines with advancing age, contributing to maldistribution of muscle blood flow during physical activity and a loss of functional capacity in the elderly. Although aerobic exercis training is commonly prescribed to counter endothelial dysfunction in the elderly, the rate of compliance to aerobic exercise training programs is low, often due to their strenuous nature. Thus, clinically-significant improvements in physical function are not obtained by many individuals placed on aerobic training programs. There is a need to develop feasible non-pharmacological interventions that enhance blood flow capacity in this population or in high-risk patients who cannot perform moderate aerobic exercise. Low-load, prolonged-duration ankle dorsiflexion, which stretches the muscles of the calf, is prescribed in patients with limited range of motion and to counter foot drop in post-stroke patients. Acute changes in muscle length alter muscle blood flow; therefore, it is likely that repeated, prolonged changes in muscle length, created by dorsiflexion splinting, alter the regulation of muscle blood flow, and represent a viable modality to augment endothelial function and functional capacity in the elderly. Our preliminary results in a rat model of aging indicate that a program of daily ankle dorsiflexion splinting dramatically improves endothelium- dependent vasodilation of resistance arteries of the soleus muscle. The overarching purpose of the proposed work is to test the hypothesis that performance of daily ankle dorsiflexion splinting improves endothelial function and lower leg muscle blood flow in the elderly. To test this hypothesis we will perform a preclinical study in aged Fischer rats (Aim 1), and clinical study in aged human subjects (Aim 2). In Aim 1, blood flow distribution to the lower hindlimb muscles will be evaluated in vivo during acute splinting and immediately following splint removal. Following 4 wks of daily splinting, hindlimb muscle blood flow will be measured at rest, and during walking exercise. Endothelial function of resistance arteries will be assessed ex vivo, and analysis of endothelial mechanisms that contribute to enhanced endothelium-dependent dilation will be investigated. In Aim 2, we will test the hypothesis that daily ankle dorsiflexion splinting (4 wks) improves endothelial function o the popliteal artery and lower leg resistance vasculature in sedentary, older human subjects. This work will determine whether a safe, non-invasive intervention (dorsiflexion splinting) can be used to improve endothelial function in elderly individuals. In addition, a program of daily dorsiflexion splinting, if shown to improve endothelial function in healthy older sedentary subjects, could be rapidly translated to clinical populations.