Continuous administration of human corticotropin-releasing hormone in the absence of glucocorticoid feedback in man

What Was Tested

Researchers studied ACTH (Corticotropin) and CRH (Corticotropin-Releasing Hormone) in this randomized controlled trial publication.

The researchers have looked at ACTH responses to saline or CRH infusions over 24 h in 6 normal subjects who, in addition, received either placebo or metyrapone, an 11 beta-hydroxylase inhibitor which blocks the formation of cortisol and thus abolishes glucocorticoid feedback.

Following metyrapone alone, absolute cortisol levels were lower but circadian rhythmicity was preserved.

Who Took Part

The abstract describes 6 subjects taking part.

The age groups tagged for this paper are adults, men only.

How the Study Was Run

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

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

As a double-blind ACTH (Corticotropin) study, the assignments were hidden from both participants and investigators until the end.

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

Cortisol and ACTH levels were measured by radioimmunoassay.

What Was Measured

Following metyrapone alone, absolute cortisol levels were lower but circadian rhythmicity was preserved.

Circadian rhythm of ACTH was maintained, with a fall in the evening to 14.5 +/- 4 pg/ml (mean +/- SE) at midnight and an exaggerated rise overnight, reaching a peak level of 90 +/- 33 pg/ml at 07:00 h.

PubMed files the paper under topics including Adrenal Cortex Hormones, Adrenocorticotropic Hormone, Corticotropin-Releasing Hormone, Feedback, Hydrocortisone, Metyrapone and Stimulation, Chemical.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of ACTH (Corticotropin) and CRH (Corticotropin-Releasing Hormone) in 6 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 1995 (Neuroendocrinology), a journal based in Switzerland.

More context: the ACTH (Corticotropin) compound page and the CRH (Corticotropin-Releasing Hormone) compound page, all human trials.