Converting enzyme inhibitors and the role of the sulfhydryl group in the potentiation of exo- and endogenous nitrovasodilators.

What Was Tested

Researchers studied Angiotensin-Converting Enzyme Inhibitors and Arginine in this randomized controlled trial publication.

The effect of captopril was not affected by pretreatment.

The involvement of endothelium-derived relaxing factor (EDRF) in the effect of captopril was apparent from experiments with L-arginine, the precursor of EDRF, and L-NMMA, the "false" precursor of EDRF.

Who Took Part

The abstract describes 10 patients taking part.

By PubMed's age tags, the people studied were middle-aged adults and older adults, men only.

How the Study Was Run

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

Because people in this Angiotensin-Converting Enzyme Inhibitors study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

Neither the patients nor the staff measuring them knew who was on Angiotensin-Converting Enzyme Inhibitors, so expectations could not easily colour the readings.

The comparison arm used a placebo, so changes seen with Angiotensin-Converting Enzyme Inhibitors could be set against what happens without it.

In the crossover set-up each of the patients took both Angiotensin-Converting Enzyme Inhibitors and the comparison in turn, acting as their own control.

What Was Measured

At day 7, a baseline exercise test was obtained.

PubMed files the paper under topics including Angina Pectoris, Angiotensin-Converting Enzyme Inhibitors, Arginine, Blood Pressure, Bradykinin, Captopril and Coronary Circulation.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Angiotensin-Converting Enzyme Inhibitors and Arginine in 10 patients.

With fewer than 40 people, it is a small study, so it is better read as an early signal for further research than as a settled answer.

The publication is from 1991 (Journal of cardiovascular pharmacology), a journal based in United States.

More context: all human trials.