CoChat
Sign Up
Cited by 84Circadian rhythm and melatoninHypothalamic control of reproductive hormonesEstrogen and related hormone effects

Estrus- and steroid-induced changes in circadian rhythms in a diurnal rodent, Octodon degus

Labyak, Susan E., Lee, Theresa M.·1995·Physiology & Behavior
DOI 10.1016/0031-9384(95)00096-2
Open this paper in CoChat — free account

Abstract

Diurnal Octodon degus exhibited marked alterations in activity and temperature in conjunction with the 3 wk estrous cycle when housed in LD12:12 light cycle. On the day of estrus, mean daily activity increases 109%, mean core temperature rises .4 degree C, activity onset is advanced 2 h, and amplitudes of both rhythms decline compared with the 3 days prior to estrus. On the day following estrus, activity onset was delayed 4.9 h, and mean activity and core temperature fell below that of the preestrus period. Ovariectomy significantly reduced mean temperature (.98 degree C) but did not significantly alter mean activity, and eliminated cyclic effects of estrus. Estrogen replacement led to a nonsignificant elevation in mean activity and core temperature with no change in the phase angle of entrainment. Progesterone replacement significantly reduced mean core temperature and mean activity, while only the phase angle difference between temperature minimum and activity onset was significantly altered. Intact degus maintained in constant darkness displayed only transient fluctuations in activity onset and temperature minimum during and after estrus. Estrogen or progesterone treatment of ovariectomized, free-running degus altered mean temperature and activity levels, but did not influence tau. Changes in phase angle of entrainment during estrus are not the result of hormone effects on the circadian clock but likely reflect increased or decreased levels of activity.

Integrity signals

Registry

Crossref · 10.1016/0031-9384(95)00096-2

Cites

38 of 38 references verified0 citation errors · 0 not checkable

Statistics

Recomputing p-values needs the paper’s full text.

Claims the paper makes

This paper’s full text isn’t openly available, so its claims and self-check weren’t run. The registry and citation checks still apply.

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Gonadal hormones can influence other circadian parameters including endogenous period, rhythm amplitude, range of entrainment, zeitgeber sensitivity, and oscillator coupling.

    “Gonadal hormones can influence other circadian parameters as well, including endogenous period [7, 23, 47, 49, 91, 129, 212], rhythm amplitude [8, 17, 100], range of entrainment [49], zeitgeber sensitivity [23, 51, 79, 81], and oscillator coupling [126, 128, 187].”

    From The neuroendocrine control of the circadian system: Adolescent chronotype (2012) · cites this paper as [100]

  • Ovariectomized adult female rodents lost the phase advance and increase in wheel running activity that typically accompanies estrus, and in general exhibited a more dispersed activity distribution and delayed activity rhythm phase.

    “This was also true of ovariectomized adult female rodents: they lost the phase advance and increase in wheel running activity that typically accompanies estrus [49, 78, 100, 129], and in general exhibited a more dispersed activity distribution and delayed activity rhythm phase [187, 203, although see 23].”

    From The neuroendocrine control of the circadian system: Adolescent chronotype (2012) · cites this paper as [100]

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Related

Authors
Labyak, S. E., & Lee, T. M.
Affiliations
University of Michigan (US)
Corresponding author
Lee, Theresa M.
ORCID
Lee, Theresa M.
Venue
Physiology & Behavior
Publisher
Elsevier BV
Published
1995-09
Volume
58
Issue
3
Pages
573-585
ISSN
0031-9384 (ISSN-L)
DOI
10.1016/0031-9384(95)00096-2
OpenAlex
W1971890281
Cited by
84
References
38
Citations by year
2025: 2 · 2022: 2 · 2021: 3 · 2020: 5 · 2019: 1 · 2018: 3 · 2017: 4 · 2016: 1 · 2015: 3 · 2014: 3 · 2013: 4 · 2012: 7
FWCI
0.92
Type
journal article
Language
en
Open access
closed
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Physiology & Behavior (publishedVersion)
  • PubMed (publishedVersion)
  • Deep Blue (University of Michigan) (submittedVersion)
Funders
  • University of Delaware
  • University of Michigan
  • Sigma Theta Tau International
  • National Institutes of Health (5r03mh049089-02, 5f31nr006397-03)
  • Horace H. Rackham School of Graduate Studies, University of Michigan
  • National Institute of Mental Health (MH49089)
  • National Institute of Nursing Research (NRO6397)
Topics
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Health Sciences › Medicine › Reproductive Medicine › Hypothalamic control of reproductive hormones
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Estrogen and related hormone effects
Keywords
Octodon degus, estrous cycle, circadian rhythm, activity rhythms, core body temperature, estrus, ovariectomy, estrogen replacement therapy, progesterone supplementation, free-running rhythm, constant darkness, diurnal rodents
MeSH terms
Animals, Body Temperature Regulation, Circadian Rhythm, Estrogens, Estrus, Female, Light, Motor Activity, Ovariectomy, Progesterone, Rodentia, Gonadal Steroid Hormones

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review