title: Effect of estradiol on plasma melatonin levels.
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) 10 micrograms/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.
mesh_terms: D000328:Adult; D004958:Estradiol; D006801:Humans; D008297:Male; D008550:Melatonin / Q000096:biosynthesis* / Q000097:blood; D010870:Pineal Gland / Q000502:physiology; D013739:Testosterone / Q000097:blood
chemical_list: D013739:Testosterone; D004958:Estradiol; D008550:Melatonin