Effect of vasopressin antagonism on renal handling of sodium and water and central and brachial blood pressure during inhibition of the nitric oxide system in healthy subjects

What Was Tested

Researchers studied Vasopressin in the context of low blood pressure and orthostatic hypotension in this randomized controlled trial publication.

The researchers wanted to test the hypotheses that tolvaptan changes both renal handling of water and sodium and systemic hemodynamics during basal conditions and during nitric oxide (NO)-inhibition with L-NG-monomethyl-arginine (L-NMMA).

Who Took Part

The age groups tagged for this paper are teenagers, young adults and adults, both men and women.

Nineteen healthy subjects were enrolled in a randomized, placebo-controlled, double-blind, crossover study of two examination days.

How the Study Was Run

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

The participants were allocated by chance, so the Vasopressin group and the comparison group should start out alike.

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

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

Each person switched between Vasopressin and the comparison at some point, usually with a gap in between.

L-NMMA was given as a bolus followed by continuous infusion during 60 minutes.

The researchers measured urine output(UO), free water clearance (CH2O), fractional excretion of sodium (FENa), urinary aquaporin-2 channels (u-AQP2) and epithelial sodium channels (u-ENaCγ), plasma vasopressin (p-AVP), central and brachial blood pressure(cBP, bBP).

What Was Measured

PubMed files the paper under topics including Antidiuretic Hormone Receptor Antagonists, Benzazepines, Blood Pressure, Body Water, Brachial Artery, Kidney and Nitric Oxide.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Vasopressin in people with low blood pressure and orthostatic hypotension.

The abstract goes on to report its results in about 8 sentences; this page does not restate them, so read the paper for the findings and their limits.

The publication is from 2014 (BMC nephrology), a journal based in England.

More context: the Vasopressin compound page, Low blood pressure and orthostatic hypotension research.