Abstract
Melatonin levels were determined in plasma samples obtained at 15 minute intervals during a 4-hour period (08:00–12:00 hours) from a normal adult male on 5 consecutive days. On days 1, 2, and 3, the subject was given estradiol valerate (E2) 10μg/kg at the end of each sampling period. An episodic pattern of melatonin secretion was found. Post E2 mean estradiol levels per 4 hours increased and mean melatonin and testosterone levels per 4 hours decreased significantly. A decrease in melatonin levels post E2 is the reverse of the response expected based on nonhuman animal experimental data.
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Martin J.E., Klein D.C. Melatonin inhibition of the neonatal pituitary response to luteinizing hormone-releasing factor. Science 191: 301, 1976.
Yamashita K., Mieno M., Shimuzu T.S., Yamashita E.R. Inhibition by melatonin of the pituitary response to luteinizing hormone releasing hormone in vivo. J. Endocrinol. 76: 487, 1977.
Cardinali D.P., Nagle C.A., Rosner J.M. Effects of estradiol on melatonin and protein synthesis in the rat pineal organ. Horm. Res. 5: 304, 1974.
Nagle C.A., Cardinali D.P., Rosner J.M. Effects of castration and testosterone administration of pineal and retinal hydroxyindole-O-methyl transferases in male rats. Neuroendocrinology 14: 14, 1974.
Weinberg U., Weitzman E.D., Fukushima D.K., Cancel G.F., Rosenfeld R.S. Melatonin does not suppress the pituitary luteinizing hormone in men. J. Clin. Endocrinol. Metab. 51: 161, 1980.
Penny R. Melatonin excretion in normal males and females: Increase during puberty. Metabolism 31: 816, 1982.
Rollag M.D., Niswender G.D. Radioimmunoassay of serum concentration of melaton in in sheep exposed to different lighting regimes. Endocrinology 98: 482, 1976.
Goebelsmann U., Bernstein G.S., Gale J.A., Kletzky O.A., Nakamura R.M., Coulson A.H., Korelitz J.J. Serum gonadotropin, testosterone, estradiol, and estrone levels prior to and following bilateral vasectomy. In: Lepow J.H., Corzier R., (Eds.), Vasectomy: immunologic and pathophysiologic effects in animals and man. Academic Press, New York, 1979, p. 165.
Goebelsmann U., Arce J.J., Thorneycroft I.H., Mishell D.R. Serum testosterone concentrations in women throughout the menstrual cycle and following HCG administration. Am. J. Obstet. Gynecol. 119: 445, 1974.
Goldstein A. Biostatistics: an introductory text. MacMillan, New York, 1968, p. 55.
Weinberg U., D’Eletto R.D., Weitzman E.D., Erlich S., Hollander C.S. Circulating melatonin in man: episodic secretion throughout the lightdark cycle. J. Clin. Endocrinol. Metab. 48: 11, 1979.
Johnson L.Y., Vaughan M.K., Richardson B.A., Petterborg L.J., Reiter R.J. Variation in pineal melatonin content the estrous cycle of the rat. Proc. Soc.Exp. Biol. Med. 169: 416, 1982.
Brown-Grant K., Exley D., Naftolin F. Peripheral plasma estradiol and luteinizing hormone concentration during the estrous cycle of the rat. J. Endocrinol. 48: 295, 1970.
Wurtman R.J., Axelrod J., Kelly D.E. The pineal. Academic Press, New York, 1968.
Cardinali D.P., Vacas M.I. Mechanism underlying hormone effects of pineal function: a model for the study of integrative neuroendocrine processes. J. Endocrinol. Invest. 7: 89, 1978.
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Supported in part by a Professional Staff Association of the Los Angeles County-University of Southern California Medical Center and by a Grant No. HD05932 from the National Institutes of Health, Bethesda, Maryland.