Effect of endothelin and BQ123 on ocular blood flow parameters in healthy subjects.

What Was Tested

Researchers studied Antihypertensive Agents in this randomized controlled trial publication.

To characterize the role of the endothelin system in the blood flow control of the optic nerve head and of the choroid in humans.

Who Took Part

The age groups tagged for this paper are adults, men only.

Two studies were performed in healthy subjects.

Measurements of optic nerve head blood flow (ONHBF) and choroidal blood flow (ChBF) were performed with laser Doppler flowmetry in both studies.

How the Study Was Run

The design is described as randomized, double-blind, placebo-controlled and crossover.

Because people in this Antihypertensive Agents study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

Neither the participants nor the staff measuring them knew who was on Antihypertensive Agents, so expectations could not easily colour the readings.

A placebo (an inactive look-alike) gave the Antihypertensive Agents group a baseline to be compared against.

In the crossover set-up each of the participants took both Antihypertensive Agents and the comparison in turn, acting as their own control.

Study 1 was a randomized, placebo-controlled, double-masked, balanced, two-way crossover design and study 2 a three way-way crossover design.

In study 2 mean flow velocity (MFV) of the ophthalmic artery was assessed with Doppler sonography.

What Was Measured

The subject headings attached to it are Antihypertensive Agents, Blood Flow Velocity, Choroid, Drug Combinations, Endothelin Receptor Antagonists, Endothelin-1 and Laser-Doppler Flowmetry.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Antihypertensive Agents.

The abstract goes on to report its results in about 6 sentences; this page does not restate them, so read the paper for the findings and their limits.

The publication is from 2001 (Investigative ophthalmology & visual science), a journal based in United States.

More context: all human trials.