These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: How does melatonin control seasonal reproductive cycles?
    Author: Arendt J, Symons AM, English J, Poulton AL, Tobler I.
    Journal: Reprod Nutr Dev (1980); 1988; 28(2B):387-97. PubMed ID: 3045925.
    Abstract:
    The pineal gland is essential for the perception of photoperiod change in many species. Information about photoperiod length is conveyed through pineal secretion of the methoxyindole melatonin. Melatonin, suitably administered in physiological quantities is equipotent with artificial photoperiod in the induction of photoperiodic responses. Most experimental work suggests that it is the duration of high night time melatonin secretion (positively correlated with the length of the natural or artificial dark phase) which conveys the photoperiodic signal. Continuous release implants induce short day effects in ewes, entirely comparable to daily feeding of melatonin or short photoperiod. A minimum duration of secretion rather than a specific duration is therefore probably critical to short day effects. There appears to be a seasonal variation in sensitivity to short day melatonin effects (induction of early oestrus) which can be shifted to an earlier time of year following one oestrus advance the previous year. Short duration melatonin is read as a long day even secreted with 22 hour periodicity, suggesting a lack of circadian variation in sensitivity to melatonin.
    [Abstract] [Full Text] [Related] [New Search]