The Circadian Rhythm of Plasma Melatonin During the Normal Menstrual Cycle and in Amenorrheic Women*
- 1 May 1988
- journal article
- research article
- Published by The Endocrine Society in Journal of Clinical Endocrinology & Metabolism
- Vol. 66 (5), 891-895
- https://doi.org/10.1210/jcem-66-5-891
Abstract
Plasma melatonin, PRL, and LH levels were measured in samples collected every 2 h for 24 h from 14 normally cycling women during the early follicular, periovulatory, and luteal phases of their menstrual cycles. Plasma melatonin levels also were measured in samples collected at the same interval from 7 patients with hypothalamic amenorrhea. A distinct daily rhythm in plasma melatonin was evident in all subjects, with peaks occurring around 0300 h. Each woman’s rhythm was remarkably consistent throughout the menstrual cycle (in terms of the phase, amplitude, and total melatonin secreted). Plasma PRL levels also exhibited daily rhythms which did not change during the menstrual cycle; the nocturnal peak plasma PRL level tended to occur 1–2 h after that for melatonin. Among the amenorrheic women, both daytime and nighttime melatonin levels were significantly higher (P < 0.005) than in the normal women. Their plasma PRL levels were similar to those in the normal women. We conclude that, as for PRL, the circadian rhythm of melatonin secretion does not change significantly during the normal menstrual cycle. The elevated plasma melatonin levels in women with hypothalamic amenorrhea suggest that the hormone may be involved in the neuroendocrine pathology underlying this disorder.Keywords
This publication has 16 references indexed in Scilit:
- FALL IN NOCTURNAL SERUM MELATONIN DURING PREPUBERTY AND PUBESCENCEThe Lancet, 1984
- Influence of Exogenous Melatonin on Melatonin Secretion and the Neuroendocrine Reproductive Axis of Intact Male Rats during Sexual Maturation*Endocrinology, 1983
- URINARY 6‐SULPHATOXY MELATONIN EXCRETION DURING THE HUMAN MENSTRUAL CYCLEClinical Endocrinology, 1982
- Melatonin and the Influence of the Pineal Gland on Timing of the LH Surge in RatsNeuroendocrinology, 1982
- Overnight Plasma Profiles of Melatonin and Certain Adenohypophyseal Hormones in Men*Journal of Clinical Endocrinology & Metabolism, 1978
- ProlactinNew England Journal of Medicine, 1978
- Effect of Melatonin on the Reproductive Systems of Male and Female Syrian Hamsters: A Diurnal Rhythm in Sensitivity to Melatonin12Endocrinology, 1976
- HUMAN SERUM MELATONIN CHANGES DURING THE MENSTRUAL CYCLEJournal of Clinical Endocrinology & Metabolism, 1976
- An Inhibitory Effect of Melatonin on the Estrous Phase of the Estrous Cycle of the RodentEndocrinology, 1964
- Melatonin, a Pineal Substance: Effect on the Rat OvaryScience, 1963