Nitric Oxide and the Autonomic Nervous System
Summary
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.
Timeline
- Start
- 2002-08
- Primary completion
- 2008-08
- Completion
- 2008-08
Publications
- Gamboa A, Shibao C, Diedrich A, Paranjape SY, Farley G, Christman B, Raj SR, Robertson D, Biaggioni I. Excessive nitric oxide function and blood pressure regulation in patients with autonomic failure. Hypertension. 2008 Jun;51(6):1531-6. doi: 10.1161/HYPERTENSIONAHA.107.105171. Epub 2008 Apr 21.
- Gamboa A, Shibao C, Diedrich A, Choi L, Pohar B, Jordan J, Paranjape S, Farley G, Biaggioni I. Contribution of endothelial nitric oxide to blood pressure in humans. Hypertension. 2007 Jan;49(1):170-7. doi: 10.1161/01.HYP.0000252425.06216.26. Epub 2006 Nov 27.
Drugs
| Evaluation | Drug | Modality | Dose | Route |
|---|---|---|---|---|
| Subject | L-NMMA | Unknown | 125 ug/kg | Intravenous |
| Subject | L-NMMA | Unknown | 250 ug/kg | Intravenous |
| Subject | L-NMMA | Unknown | 500 ug/kg | Intravenous |
| Background | Trimethaphan | Small molecule | 4 mg | Intravenous |
| Background | Trimethaphan | Small molecule | 6 mg | Intravenous |