Study of the Response of Human Small Blood Vessels

NCT00001622 | Completed Phase 1

• 2 other identifiers: 97009897-H-0098
• Study Type: interventional
• Target: 87
• Locations: 1 country
• Sites: 1

Brief Summary

A layer of cells called the endothelium line the walls of blood vessels. These cells produce substances that control the tone of blood vessels and thus control blood flow through the vessel. One of the substances produced involved in the control of blood vessel function is nitric oxide. Nitric oxide (NO) plays a role in the relaxation of blood vessels. Researchers have been interested in the function of the endothelium in patients with high blood pressure (essential hypertension) and patients with high cholesterol (hypercholesterolemia). After conducting studies on the endothelium and nitric oxide, researchers have found that the endothelium is indeed functioning abnormally in patients with high blood pressure and high cholesterol. In addition, researchers have determined that the dysfunction is a result of abnormalities in the nitric oxide (NO) system. In this study researchers plan to investigate the relationship between blood vessel responses in real-life settings versus laboratory settings in normal volunteers, patients with high blood pressure, and patients with high cholesterol.

Conditions

Healthy; Hypercholesterolemia; Hypertension

Keywords

Endothelium; Hypercholesterolemia; Hypertension; Microvessels; Vasodilation; Normal Volunteer

Interventions

investigate the relationship between in vivo and in vitro vascular responses PROCEDURE

Eligibility Criteria

• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

Patients (men and nonpregnant women) with systemic hypertension, patients with hypercholesterolemia, and normal volunteers. All blood pressure recordings must be consistently elevated. No renovascular hypertension or other etiologies for elevated blood pressure. No definite evidence of accelerated or malignant hypertension (diastolic pressures above 115 mmHg, with associated encephalopathic changes, papilledema, progressive renal failure, or congestive heart failure), or serious intercurrent illness. Patients in whom withdrawal of antihypertensive medications is considered hazardous are ineligible. Patients in whom the blood pressure remains at normal levels 2 weeks after withdrawal of antihypertensive treatment will be closely monitored until they become hypertensive, at which time they will undergo the study. Patients in whom blood pressure does not increase after 2 months of discontinuation of therapy will be excluded from the study. Patients with coexistent hypertension and hypercholesterolemia are ineligible. Normal volunteers who are not taking any kind of medication are eligible. No history of diabetes, peripheral vascular disease, coagulopathy, or any other disease predisposing to vasculitis or Raynaud's phenomenon. No history of keloid formation. All patients must be capable of giving informed consent for all procedures.

Contact the study team to discuss eligibility requirements. They can help determine if this study is right for you.

Sponsors & Collaborators

• National Heart, Lung, and Blood Institute (NHLBI): lead

Study Sites (1)

National Heart, Lung and Blood Institute (NHLBI)

Bethesda, Maryland, 20892, United States

Location

Related Publications (3)

• Furchgott RF. Role of endothelium in responses of vascular smooth muscle. Circ Res. 1983 Nov;53(5):557-73. doi: 10.1161/01.res.53.5.557. No abstract available.

  PMID: 6313250 BACKGROUND

• Falloon BJ, Heagerty AM. In vitro perfusion studies of human resistance artery function in essential hypertension. Hypertension. 1994 Jul;24(1):16-23. doi: 10.1161/01.hyp.24.1.16.

  PMID: 8021003 BACKGROUND

• Goode GK, Heagerty AM. In vitro responses of human peripheral small arteries in hypercholesterolemia and effects of therapy. Circulation. 1995 Jun 15;91(12):2898-903. doi: 10.1161/01.cir.91.12.2898.

  PMID: 7796498 BACKGROUND

MeSH Terms

Conditions

Hypercholesterolemia; Hypertension; Aneurysm

Condition Hierarchy (Ancestors)

Hyperlipidemias; Dyslipidemias; Lipid Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Vascular Diseases; Cardiovascular Diseases

Study Design

• Study Type: interventional
• Phase: phase 1
• Purpose: TREATMENT
• Sponsor Type: NIH

Study Record Dates

• First Submitted: November 3, 1999
• First Posted: December 10, 2002
• Study Start: March 1, 1997
• Study Completion: March 1, 2001
• Last Updated: March 4, 2008

Record last verified: 2000-01

Locations

US (1)