Cardiovascular Regulation: Autonomic/Metabolic Mechanisms PO1 HL56693, Project 4: Cardiovascular Regulation: Autonomic/Metabolic Mechanisms
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 112
- 试验地点
- 1
- 主要终点
- Change in Systolic Blood Pressure
研究概览
简要总结
The amount of blood flowing to the different parts of the body is regulated by the autonomic (automatic) nerves and by local factors produced by the blood vessels. Nitric oxide (NO) is one of the most important of these metabolic factors. If the production of NO is slowed or stopped the amount of blood to the different parts of the body is decreased. There is increasing knowledge that NO mechanisms are impaired in a number of medical conditions. NO function is reduced in patients with risk factors for atherosclerosis (hardening of the arteries) such as hypercholesterolemia (patients with high cholesterol), or diabetes mellitus, and is also impaired in smokers. This NO "deficiency" is believed to contribute to the greater cardiovascular risk that marks these patient populations. This study is designed to examine if endothelial nitric oxide is an important control mechanism of blood pressure under normal conditions, and if impairment of nitric oxide contributes to hypertension.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Adult subjects.
- •18 to 85 years.
- •Non-smokers or long term smokers for specific aim
- •Drug-free.
- •Long term hypertension in specific substudy 3, patients with autonomic failure in specific aims 4 and 5, diabetes mellitus in specific aim 5.
排除标准
- •Being on any medication other than antihypertensives (for hypertensives), autonomic medications (for autonomic failure [AF] patients), insulin or other treatment for diabetes (for diabetic patients).
- •Having pulmonary, renal, hematopoietic, hepatic and/or cardiac disease.
研究组 & 干预措施
Autonomic Failure Patients
To compare the effects of NO inhibition during intact and transient pharmacological blockade of the autonomic nervous system in Patients with Autonomic Failure.
干预措施: L-NMMA (Drug)
Autonomic Failure Patients
To compare the effects of NO inhibition during intact and transient pharmacological blockade of the autonomic nervous system in Patients with Autonomic Failure.
干预措施: Trimethaphan (Drug)
Controls and hypertensives
To compare the effects of NO inhibition during intact and transient pharmacological blockade of the autonomic nervous system in normal volunteers and hypertensive subjects.
干预措施: L-NMMA (Drug)
Controls and hypertensives
To compare the effects of NO inhibition during intact and transient pharmacological blockade of the autonomic nervous system in normal volunteers and hypertensive subjects.
干预措施: Trimethaphan (Drug)
结局指标
主要结局
Change in Systolic Blood Pressure
时间窗: At the end of the highest tolerated dose of IV infusion of L-NMMA
L-NMMA (nitric oxide synthase inhibitor) was infused intravenously at different doses for 15 minutes each, after blocking the autonomic nervous system with trimethaphan. The change in systolic blood pressure at the end of the highest tolerated dose is the main outcome. Trimethaphan infused intravenously was used to produce transient blockade of the autonomic nervous system to allow for a full response to nitric oxide inhibition (in the absence of the baroreflex.
Systolic Blood Pressure in Response to Systemic Nitric Oxide Inhibition
时间窗: End of 15 minutes of infusion of L-NMMA at the highest tolerated dose
Systolic blood pressure at the highest tolerated dose of IV infusion of L-NMMA during autonomic nervous system blockade with trimethaphan. Trimethaphan, infused intravenously was used to produce transient blockade of the autonomic nervous system to allow for a full response to nitric oxide inhibition (in the absence of the baroreflex.
次要结局
未报告次要终点
研究者
Italo Biaggioni
Professor of Medicine
Vanderbilt University