The Role of Angiotensin Type I Receptor in the Regulation of Human Peripheral Vascular Function

Phase 3

Completed

• Conditions: Atherosclerosis; Heart Failure, Congestive; Hypertension; Myocardial Infarction

• Registration Number: NCT00001628
• Lead Sponsor: National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary

The renin angiotensin system (RAS) plays an important physiological and pathophysiological role in the control of blood pressure and plasma volume. Inhibition of the RAS is useful in the treatment of hypertension, cardiac failure and in some patients with myocardial infarction. Several recent clinical trials with angiotensin converting enzyme inhibitors (ACEI) have shown that they also reduce the incidence of myocardial infarction, but the mechanisms underlying this anti-ischemic effect are poorly understood. ACEI reduce angiotensin II synthesis and prevent bradykinin degradation. Results from ongoing studies in the Cardiology Branch (Protocol 95-H-0099) designed to investigate the link between ACEI and the vascular endothelium indicate that ACEI improve peripheral endothelial function, an effect that is partially mediated by bradykinin. The current protocol is designed to investigate whether the beneficial effects of ACEI on peripheral endothelial function are also due to inhibition of angiotensin II. The recent development of selective angiotensin II type 1 (AT1) receptor antagonists allows us to specifically examine the effects of angiotensin II on vasomotor activity.

Detailed Description

The renin angiotensin system (RAS) plays an important physiological and pathophysiological role in the control of blood pressure and plasma volume. Inhibition of the RAS is useful in the treatment of hypertension, cardiac failure and in some patients with myocardial infarction. Several recent clinical trials with angiotensin converting enzyme inhibitors (ACEI) have shown that they also reduce the incidence of myocardial infarction, but the mechanisms underlying this anti-ischemic effect are poorly understood. ACEI reduce angiotensin II synthesis and prevent bradykinin degradation. Results from ongoing studies in the Cardiology Branch (Protocol 95-H-0099) designed to investigate the link between ACEI and the vascular endothelium indicate that ACEI improve peripheral endothelial function, an effect that is partially mediated by bradykinin. The current protocol is designed to investigate whether the beneficial effects of ACEI on peripheral endothelial function are also due to inhibition of angiotensin II. The recent development of selective angiotensin II type 1 (AT1) receptor antagonists allows us to specifically examine the effects of angiotensin II on vasomotor activity.

Study Timeline

• Study Start: 1997-07
• Status Verified: 1999-06
• Study First Submitted: 1999-11-03
• Study Completion: 2000-09
• Study First Submitted QC: 2002-12-09
• Study First Posted: 2002-12-10
• Last Update Submitted: 2008-03-03
• Last Update Posted: 2008-03-04

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 36

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: Not specified

Trial Locations

Locations (1)

National Heart, Lung and Blood Institute (NHLBI); 🇺🇸 Bethesda, Maryland, United States