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Published on: November 11, 2016

Circadian rhythm in plasma immunoreactive somatomedin-C in children

G Y Nicolau, E Haus, D Lakatua

    Endocrinologie
    |April 1, 1985
    PubMed

    Insights

    This study reveals distinct daily rhythms for somatomedin-C, growth hormone, and cortisol in children. These hormonal circadian patterns, with somatomedin-C peaking in the evening, offer insights into physiological regulation and clinical assessments.

    Area of Science:

    • Pediatric Endocrinology
    • Chronobiology
    • Hormone Physiology

    Background:

    • Circadian rhythms significantly influence various physiological processes in children.
    • Understanding the daily fluctuations of key hormones like somatomedin-C, growth hormone, and cortisol is crucial for accurate clinical interpretation.

    Purpose of the Study:

    • To investigate the circadian rhythms of plasma immunoreactive somatomedin-C (SM-C), growth hormone (hGH), and cortisol in prepubertal children.
    • To compare the timing of peak concentrations for these hormones over a 24-hour period.

    Main Methods:

    • Blood samples were collected over 24 hours from 15 boys and 27 girls (aged 11 +/- 2 years) in June.
    • Plasma concentrations of immunoreactive SM-C, hGH, and cortisol were measured.
    • Statistical analysis was used to identify significant circadian rhythms and acrophases.

    Main Results:

    • Statistically significant circadian rhythms were observed for SM-C, hGH, and cortisol.
    • SM-C peaked in the early evening (acrophase 19:08).
    • hGH peaked during the night, while cortisol peaked in the morning hours, demonstrating distinct temporal patterns.

    Conclusions:

    • Children exhibit distinct circadian rhythms for SM-C, hGH, and cortisol with differing acrophases.
    • These findings are important for understanding the physiological regulation of SM-C.
    • The results aid in the clinical evaluation of SM-C concentrations and responses to hormonal manipulation.

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