AGING, LIMB VASCULAR RESISTANCE, AND SYMPATHETIC TONE

衰老、四肢血管阻力和交感神经张力

• 批准号: 6453528
• 负责人: Kerrie Moreau
• 金额: $ 2.85万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-10-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6453528
• 关键词: age difference; aging; alpha antiadrenergic agent; blood circulation; blood flow measurement; clinical research; human subject; limbs; ultrasonography; vascular resistance; vascular smooth muscle nervous control; vasomotion

DESCRIPTION (Applicant's abstract):Systemic vascular resistance (SVR) increase with advancing age even in healthy humans. Augmented vasoconstriction in the limb vasculature contributes to the age-related elevation in SVR and thus, an elevated sympathetic alpha-adrenergic vasoconstrictor tone could be a mechanism contributing to the increase in SVR with age. The primary aim of the present proposal is to test the hypothesis that tonic increases in sympathetic alpha-adrenergic vasoconstriction contribute to the elevation in limb vascular resistance with age. To address this aim, arterial blood pressure, femoral (whole-leg) blood flow (high resolution ultrasonography), and plasma catecholamines will be determined under resting baseline conditions and after local alpha-adrenergic blockade (intra-arterial infusions of phentolamine). Other measurements will include muscle sympathetic nerve activity (microneurography), leg tissue mass (DEXA), and femoral artery structure (ultrasound). The results of the proposed study should provide new and clinically important information concerning the role of sympathetic-adrenergic mechanisms in age-related elevations in limb vascular resistance.

描述（申请人的摘要）：全身血管抵抗（SVR）增加 随着年龄的增长，即使在健康的人类中也是如此。增强血管收缩 肢体脉管系统有助于SVR中与年龄相关的海拔 提高的交感神经 - 肾上腺素能血管收缩的音调可能是一种机制 随着年龄的增长而导致SVR的增加。现在的主要目的 提案是测试滋补性增长同情的假设 α-肾上腺素能血管收缩有助于肢体血管的升高 随着年龄的增长的抵抗。为了解决这一目标，动脉血压，股骨 （全腿）血流（高分辨率超声检查）和等离子体 儿茶酚胺将在静止基线条件下和之后确定 局部α-肾上腺素能阻断（苯丙胺的动脉内输注）。 其他测量将包括肌肉交感神经活动 （微功能学），腿部组织质量（DEXA）和股动脉结构 （超声波）。拟议研究的结果应提供新的和 临床上重要的信息有关交感神经 - 肾上腺素能的作用 肢体血管抗性与年龄相关的高程机制。