Peripheral Vascular Effects of Sulfhydryl-containing Antihypertensive Pharmacotherapy on Microvessels in Humans

Summary

High blood pressure can cause physical changes to the blood vessels of the body (remodeling). If a person who has high blood pressure also has a lot of blood vessel remodeling with their condition, they are more likely to have poor results with medical treatment for hypertension. The researchers examine the impact of different classes of drugs that doctors use to treat high blood pressure (hypertension) on blood vessel remodeling. Some drugs that doctors prescribe for their patients contain a "sulfhydryl group" (a sulfur atom bonded to a hydrogen atom). Drugs that have the sulfhydryl group may reduce blood vessel remodeling more that drugs that do not. For this study, participants who have high blood pressure perform the experiments, take a drug for 16-weeks to lower blood pressure, and repeat the experiments. The researchers randomly assign one of three drugs to participants who have high blood pressure: a diuretic ("water pill"), a drug containing a sulfhydryl (SH) group, or a drug that does not contain a sulfhydryl group. Participants who do not have high blood pressure perform the experiments, but do not take any of the drugs. In some of our experiments, the researchers use a technique called "microdialysis" (MD). With MD, the researchers perfuse some research drugs into the skin on the forearm through tiny tubing that mimics capillaries. These MD drugs mimic or block substances the body naturally makes to control the small blood vessels in the skin. The drugs remain in nickel-sized areas around the tubing and do not go into the rest of the body. The researchers also analyze very small skin samples (skin biopsy) obtained from the forearm. Lastly, the researchers use a standard technique called "flow mediated dilation" (FMD) that uses blood pressure cuffs and ultrasound to look at the health of larger blood vessels in the body. FMD includes placing a small tablet of nitroglycerin under the tongue during part of the test.

Conditions

• Hypertension,Essential

Interventions

DRUG

Captopril Pill

ACEi+SH

DRUG

Enalapril Pill

ACEi

DRUG

Hydrochlorothiazide

diuretic

Sponsors & Collaborators

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

  collaborator NIH

• Penn State University

  lead OTHER

Principal Investigators

• Lacy M Alexander, PhD · Penn State University

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

40 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2016-07-20

Primary Completion

2022-08-31

Completion

2022-12-31

FDA Drug

Yes

Countries

• United States

Study Locations