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Related Concept Videos

Circadian Rhythms and Gene Regulation02:19

Circadian Rhythms and Gene Regulation

The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
Circadian Rhythms and Gene Regulation02:19

Circadian Rhythms and Gene Regulation

The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
Biological Clocks and Seasonal Responses02:45

Biological Clocks and Seasonal Responses

The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response01:15

Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response

Circadian rhythms are cyclic changes that are crucial in plasma drug concentrations. Various standard circadian parameters, including core body temperature, heart rate, and other cardiovascular factors, directly impact disease states and the therapeutic response to drug therapy.
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Hormonal Regulation of the Menstrual Cycle01:22

Hormonal Regulation of the Menstrual Cycle

The ovarian cycle regulates endometrial changes throughout a single menstrual cycle via the coordinated action of gonadotrophin-releasing hormone (GnRH) and gonadotrophins.
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
Hormonal Control of the Ovarian Cycle01:30

Hormonal Control of the Ovarian Cycle

The ovarian cycle is meticulously regulated by the hypothalamic-pituitary-gonadal axis. This cycle orchestrates the release of a mature oocyte, essential for reproduction.
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle.  At puberty, GnRH secretion increases in both frequency and...

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Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
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Published on: November 11, 2016

Circadian rhythms and reproduction.

Michael J Boden1, David J Kennaway

  • 1Research Centre for Reproductive Health, Discipline of Obstetrics and Gynaecology, School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, South Australia 5005, Australia.

Reproduction (Cambridge, England)
|August 31, 2006
PubMed
Summary

The circadian timing system and clock genes influence reproductive function. While redundancies exist, primary clock genes Clock and Bmal1 are crucial for reproductive competency in animals and potentially humans.

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Area of Science:

  • Chronobiology
  • Reproductive Biology
  • Genetics

Background:

  • The circadian timing system, regulated by clock genes, impacts numerous physiological systems.
  • Gene expression in key organs like the suprachiasmatic nucleus, liver, heart, and kidney is significantly influenced by circadian rhythms.

Purpose of the Study:

  • To review the role of circadian rhythmicity and clock genes in controlling reproductive function in both animals and humans.
  • To highlight the emerging evidence linking primary clock genes, Clock and Bmal1, to reproductive competency.

Main Methods:

  • Review of existing literature on circadian rhythms and reproductive function.
  • Analysis of microarray studies showing circadian-influenced gene expression.
  • Examination of knockout mouse models and strain differences in Clock mutant studies.

Main Results:

  • Circadian rhythms and clock genes appear essential for optimal reproductive performance, though functional redundancies mask effects in some knockout models.
  • Significant strain-specific differences observed in Clock mutant mice.
  • Emerging evidence indicates Clock and Bmal1 strongly influence reproductive competency.

Conclusions:

  • The circadian timing system plays a significant role in reproductive function, with Clock and Bmal1 being key regulators.
  • The impact of the circadian timing system on human reproduction requires further investigation.
  • Polymorphisms in Clock and Bmal1 warrant study in relation to human infertility.