Melatonin as a local regulator of human placental function

Shinya Iwasaki, Kazumi Nakazawa, Jun Sakai, Kunio Kometani, Mitsutoshi Iwashita, Yasunori Yoshimura, Tetsuo Maruyama

Research output: Contribution to journalArticlepeer-review

74 Citations (Scopus)


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.

Original languageEnglish
Pages (from-to)261-265
Number of pages5
JournalJournal of Pineal Research
Issue number3
Publication statusPublished - 2005 Oct
Externally publishedYes


  • Human chorionic gonadotropin
  • Melatonin
  • Placenta
  • Trophoblast

ASJC Scopus subject areas

  • Endocrinology


Dive into the research topics of 'Melatonin as a local regulator of human placental function'. Together they form a unique fingerprint.

Cite this