title: Maternal-fetal transfer of melatonin in pregnant women near term.
abstract: Our objective was to evaluate the maternal-fetal transfer of melatonin in pregnant women. Serum melatonin concentration was measured by high-performance liquid chromatography with electrochemical detection in a maternal vein and in the umbilical artery and umbilical vein at the time of birth. Blood samples were obtained from 12 women who had spontaneously delivered vaginally at night. A single oral dose of melatonin was administered to each of 33 patients who underwent a cesarean section, and, blood samples were taken at 1, 2, 3, or 4 hr after the administration of melatonin at delivery. Cesarean section was performed between 1300 and 1500 hr. The mean melatonin concentrations of melatonin in maternal peripheral venous blood and umbilical arterial and umbilical venous blood did not differ significantly, and positive correlations in the serum levels of melatonin were observed between the three sources of blood. The oral administration of 3 mg of melatonin to pregnant women led to marked increases in the serum levels of melatonin, with maximum levels observed 2 hr (21.84 +/- 2.09 ng/ml) after drug administration. Changes in serum levels of melatonin in the umbilical vein and artery resembled those found in the maternal vein. Serum melatonin concentrations did not differ significantly between the maternal vein and the umbilical veins. Serum levels of melatonin in the umbilical vein after the administration of melatonin were significantly and closely correlated with those in the maternal vein (r = 0.924, P < 0.001). These results suggest that, in humans, melatonin is transferred from the maternal to the fetal circulation both easily and rapidly. A potential for the therapeutic use of melatonin as an antioxidant exists in the patients with preeclampsia.
authors.affiliation: Department of Obstetrics and Gynecology, Kochi Medical School, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Okatani
authors.forename: K
authors.initials: K
authors.lastname: Okamoto
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.forename: A
authors.initials: A
authors.lastname: Wakatsuki
authors.forename: S
authors.initials: S
authors.lastname: Tamura
authors.forename: Y
authors.initials: Y
authors.lastname: Sagara
mesh_terms: D000293:Adolescent; D000328:Adult; D001692:Biological Transport; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D005865:Gestational Age; D006801:Humans; D008431:Maternal-Fetal Exchange; D008550:Melatonin / Q000493:pharmacokinetics*; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D014469:Umbilical Arteries / Q000378:metabolism; D014471:Umbilical Veins / Q000378:metabolism
chemical_list: D008550:Melatonin