Assessment of microvascular leakage via sputum induction: the role of substance P and neurokinin A in patients with asthma

What Was Tested

Researchers studied Substance P in this randomized controlled trial publication.

The aim of this study was to determine the effect of inhaled substance P, a potent neurokinin 1 (NK1) agonist and mediator of plasma extravasation, on markers of microvascular leakage in induced sputum from patients with asthma.

Why It Was Studied

Microvascular leakage is an important feature of inflammation.

However, the assessment of vascular leakage has seldom been used to monitor airway inflammation in asthma.

Who Took Part

The study group was 12 subjects.

By PubMed's age tags, the people studied were adults, both men and women.

How the Study Was Run

In design terms this was a randomized, single-blind and crossover study.

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

In this single-blind Substance P study one party knew the assignments and the other did not.

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

What Was Measured

However, the assessment of vascular leakage has seldom been used to monitor airway inflammation in asthma.

The levels of alpha2-macroglobulin, ceruloplasmin, albumin, and fibrinogen were determined in induced sputum as markers of leakage.

Topics PubMed links to this paper include Albumins, Asthma, Biomarkers, Capillary Permeability, Ceruloplasmin, Fibrinogen and Neurokinin A.

What This Means in Plain Language

The paper is a randomized, single-blind and crossover study of Substance P in 12 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.

The publication is from 2002 (American journal of respiratory and critical care medicine), a journal based in England.

More context: the Substance P compound page, all human trials.