This Article Full Text Full Text (PDF) All Versions of this Article: 136/5/533    most recent REP-08-0202v1 Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fujinoki, M. Search for Related Content PubMed PubMed Citation Articles by Fujinoki, M.

Melatonin-enhanced hyperactivation of hamster sperm

Department of Physiology, School of Medicine, Dokkyo Medical University, Mibu, Tochigi 321-0293, Japan

Correspondence should be addressed to M Fujinoki; Email: fujinoki{at}dokkyomed.ac.jp

The effects of melatonin on reproductive function were examined using hamster spermatozoa. When 1 pM to 1 µM melatonin was added to the mTALP medium, hyperactivation was significantly enhanced. Antagonists and agonists of the melatonin receptor (i.e., MT1 and MT2) were added to the medium. Luzindole, an MT1 and MT2 competitive antagonist, significantly inhibited melatonin-induced hyperactivation, whereas the MT2-specific antagonists, 4-phenyl-2-propionamidotetralin and N-pentanoyl-2-benzyltryptamine, had no effect. Moreover, hyperactivation was significantly enhanced when non-specific agonists, such as 6-chloromelatonin and 2-iodomelatonin, were added to the medium. 8-Methoxy-2-propionamidotetralin, which is a strong MT2 agonist and a weak MT1 agonist, significantly increased hyperactivation, although the effect was weak. Therefore, it is likely that melatonin enhances sperm hyperactivation via the MT1 receptor.

This article has been cited by other articles:

				R. J. Reiter, D.-X. Tan, L. C. Manchester, S. D. Paredes, J. C. Mayo, and R. M. Sainz Melatonin and Reproduction Revisited Biol Reprod, September 1, 2009; 81(3): 445 - 456. [Abstract] [Full Text] [PDF]