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Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Synchronization of hormonal time series: analytical approaches
G R Merriam1, K W Wachter, N Ma
1Developmental Endocrinology Branch, NICHHD, Bethesda, Maryland.
Acta Paediatrica Scandinavica. Supplement
|January 1, 1991
Summary
This study introduces a new method to analyze hormone secretion patterns, finding significant simultaneous peaks between luteinizing hormone (LH) and prolactin in normal subjects. This method also revealed higher LH and prolactin coincidence in hypogonadotrophic men treated with GnRH.
Area of Science:
- Endocrinology
- Chronobiology
- Biostatistics
Background:
- Simultaneous hormone measurements often show apparent peak synchrony, but chance occurrences can be misleading.
- Traditional cross-correlation methods are inadequate for analyzing ultradian hormone secretion peaks.
- A novel statistical approach is needed to accurately assess temporal relationships between discrete hormone pulses.
Purpose of the Study:
- To develop and validate a new statistical method for identifying significant coincidences in episodic hormone secretion.
- To apply this method to analyze the temporal relationship between luteinizing hormone (LH) and prolactin pulses.
- To compare coincidence rates in normal subjects, hypogonadotrophic men treated with GnRH, and control (mismatched) series.
Main Methods:
- Hormone secretion peaks were identified as discrete events.
- The frequency of simultaneous and near-simultaneous peaks was quantified within temporal windows.
- Coincidence rates were compared between actual hormone pairs and deliberately 'mismatched' series to assess random chance.
Main Results:
- A significant excess of simultaneous luteinizing hormone (LH) and prolactin peaks was observed in normal subjects (17%) compared to mismatched controls (6%).
- Hypogonadotrophic men receiving pulsatile gonadotrophin-releasing hormone (GnRH) treatment exhibited an even higher LH-prolactin coincidence rate (26%).
- No significant coincidence excess was found between LH and cortisol pulses beyond chance levels.
Conclusions:
- The proposed event-based method accurately detects non-random synchrony in episodic hormone secretion.
- LH and prolactin secretion exhibit significant temporal coupling in normal individuals and is enhanced by GnRH treatment.
- This approach provides a robust tool for analyzing ultradian rhythms and hormonal interactions.
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