title: Melatonin as a local regulator of human placental function.
abstract: Melatonin plays a critical role in a variety of mammalian reproductive processes not only acting on the central nervous system but also behaving as a peripheral physiologic regulator. To address the relevance of melatonin to the maintenance of pregnancy at the feto-maternal interface, we investigated the expression of two types of membrane melatonin receptors, MT1 and MT2, as well as arylalkylamine N-acetyltransferase (AA-NAT) and hydroxyindole-O-methyltransferase (HIOMT), the two enzymes required for the conversion of serotonin to melatonin, in the human placenta and the effect of melatonin on the release of human chorionic gonadotropin (hCG) from cultured human trophoblast cells. RT-PCR analysis and DNA sequencing revealed that transcripts of MT1, MT2, AA-NAT, and HIOMT were present in the first-trimester human placenta. We also found that melatonin significantly potentiated hCG secretion at optimal concentrations. These results suggest that melatonin may regulate human placental function in a paracrine/autocrine manner, providing evidence for a novel role in human reproduction.
authors.affiliation: Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Iwasaki
authors.forename: Kazumi
authors.initials: K
authors.lastname: Nakazawa
authors.forename: Jun
authors.initials: J
authors.lastname: Sakai
authors.forename: Kunio
authors.initials: K
authors.lastname: Kometani
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Iwashita
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Maruyama
mesh_terms: D000121:Acetylserotonin O-Methyltransferase / Q000096:biosynthesis / Q000235:genetics; D047068:Arylalkylamine N-Acetyltransferase / Q000096:biosynthesis / Q000235:genetics; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000378:metabolism; D005260:Female; D006801:Humans; D008550:Melatonin / Q000502:physiology*; D010920:Placenta / Q000201:enzymology / Q000378:metabolism / Q000502:physiology*; D011247:Pregnancy; D012333:RNA, Messenger / Q000302:isolation & purification; D044094:Receptors, Melatonin / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014327:Trophoblasts / Q000378:metabolism
chemical_list: D006063:Chorionic Gonadotropin; D012333:RNA, Messenger; D044094:Receptors, Melatonin; D000121:Acetylserotonin O-Methyltransferase; D047068:Arylalkylamine N-Acetyltransferase; D008550:Melatonin