Endothelin ETA receptor-subtype specific antagonism does not mitigate the acute systemic or renal effects of exogenous angiotensin II in humans

What Was Tested

The paper reports a study of Angiotensin II, published as a randomized controlled trial.

The aim of the present study was to investigate whether the acute effects of Ang II on systemic and renal haemodynamics in healthy subjects can be influenced by endothelin ET(A)-receptor blockade.

Why It Was Studied

Angiotensin II (Ang II) is assumed to play a pathophysiological role in a variety of vascular diseases.

Animal studies indicate that these effects are partly attributed to stimulation of endothelin-1 (ET-1) release.

Who Took Part

According to the abstract, 10 subjects were involved.

By PubMed's age tags, the people studied were adults, men only.

The study design was balanced, randomized, placebo-controlled, double blind, two-way cross-over, in 10 healthy male subjects.

How the Study Was Run

The researchers set it up as a randomized, double-blind, placebo-controlled and crossover study.

Random assignment meant chance, not the researchers, decided who got Angiotensin II and who got the comparison, which limits bias.

Blinding on both sides kept the subjects and researchers unaware of who received Angiotensin II.

Some subjects received a placebo instead of Angiotensin II, giving a reference point.

In the crossover set-up each of the subjects took both Angiotensin II and the comparison in turn, acting as their own control.

Renal plasma flow (RPF) and glomerular filtration rate (GFR) were assessed by the para-aminohippurate and inulin plasma clearance method, respectively.

Renal vascular resistance (RVR) was calculated from mean arterial pressure (MAP) and renal plasma flow.

What Was Measured

The subject headings attached to it are Angiotensin II, Endothelin Receptor Antagonists, Endothelin-1, Glomerular Filtration Rate, Hemodynamics, Inulin and Peptides, Cyclic.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Angiotensin II in 10 subjects.

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.

Its findings take up roughly 5 sentences of the abstract and are left out here on purpose; the source paper is the place to read them.

The publication is from 2002 (European journal of clinical investigation), a journal based in England.

More context: the Angiotensin II compound page, all human trials.