Cited by 21Circadian rhythm and melatoninAdrenal Hormones and DisordersStress Responses and Cortisol

Analysis of circadian periodicity of plasma cortisol in normal man and in Cushing's syndrome

Vagnucci, A. H.·1979·American Journal of Physiology-Regulatory, Integrative and Comparative Physiology

Abstract

In normal subjects, adjusted to a circadian environment, half-hourly plasma cortisol levels over a 24-h span (time series, TS) outline a circadian sinusoidal pattern that may be masked by superimposed short-lived oscillations. The periodogram objectively defines the features (amplitude, phase) of this pattern in individual TS and, more efficiently, in the average and concatenation of homogeneous TS. Concatenation is a procedure by which homogeneous short TS are attached one after the other. Homogeneity is inferred by variance analysis and by a new measure, h, with statistical significance, derived from the spectrum of the concatenated TS. Through concatenation, autocovariance for periodicity identification becomes possible. The TS from three groups of volunteers are highly homogeneous and have a predominant, statistically significant amplitude with peak time near 1100 h. The patterns from patients with Cushing's disease differ markedly in their means and periodic features; by the above criteria, we identify a subgroup with significant h measure and 24-h amplitude. This analysis provides a tool for investigation of the circadian clock in man.

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Crossref · 10.1152/ajpregu.1979.236.5.r268

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Authors
Vagnucci, A. H.
Corresponding author
Vagnucci, A. H.
Venue
American Journal of Physiology-Regulatory, Integrative and Comparative Physiology
Published
1979-05-01
Volume
236
Issue
5
Pages
R268-R281
ISSN
  • 0363-6119 (ISSN-L)
  • 1522-1490
OpenAlex
W2211643663
Cited by
21
References
0
Citations by year
2020: 2
FWCI
0.77
Type
journal article
Language
en
Open access
closed
Locations
  • American Journal of Physiology-Regulatory, Integrative and Comparative Physiology (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Adrenal Hormones and Disorders
  • Life Sciences › Neuroscience › Behavioral Neuroscience › Stress Responses and Cortisol
Keywords
circadian rhythm, plasma cortisol, Cushing's disease, Cushing's syndrome, periodogram, time series homogeneity, circadian clock
MeSH terms
Adolescent, Adrenal Glands, Adult, Analysis of Variance, Circadian Rhythm, Cushing Syndrome, Diet, Female, Humans, Hydrocortisone, Male, Sodium Chloride

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