Reduced responsiveness to endothelin-1 in peripheral resistance vessels of patients with syndrome X

What Was Tested

Researchers studied Endothelin-1 in this randomized controlled trial publication.

This study sought to assess the contribution and action of nitric oxide and endothelin-1 in peripheral resistance vessels of patients with syndrome X.

Why It Was Studied

Patients with syndrome X may have a generalized disorder of vascular and endothelial function, promoting vasospasm.

Who Took Part

The study group was 10 patients.

PubMed indexes the participants as middle-aged adults, both men and women.

Changes in blood flow responses to intrabrachial infusion of the endothelium-dependent vasodilators substance P and acetylcholine, the endothelium-independent nitric oxide donor sodium nitroprusside and the endothelin type A (ET(A)) receptor antagonist BQ-123 were assessed using venous occlusion plethysmography in 10 patients with syndrome X and 10 matched control subjects.

How the Study Was Run

In design terms this was a randomized study.

The patients were allocated by chance, so the Endothelin-1 group and the comparison group should start out alike.

Vasoconstrictor responses to the nitric oxide synthase inhibitor L-N(G)-monomethyl arginine (L-NMMA) and endothelin-1 were also determined.

What Was Measured

PubMed files the paper under topics including Analysis of Variance, Endothelin Receptor Antagonists, Endothelin-1, Enzyme Inhibitors, Microvascular Angina, Nitric Oxide and Nitroprusside.

What This Means in Plain Language

The paper is a randomized study of Endothelin-1 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.

Results are reported in around 5 sentences of the abstract; we leave them to the paper itself rather than summarise them.

The publication is from 1998 (Journal of the American College of Cardiology), a journal based in United States.

More context: the Endothelin-1 compound page, all human trials.