Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1999-9-30
pubmed:abstractText
Many mammalian species from temperate latitudes exhibit seasonal variations in breeding activity which are controlled by the annual photoperiodic cycle. Photoperiodic information is conveyed through several neural relays from the retina to the pineal gland where the light signal is translated into a daily cycle of melatonin secretion: high at night, low in the day. The length of the nocturnal secretion of melatonin reflects the duration of the night and it regulates the pulsatile secretion of gonadotropin-releasing hormone (GnRH) from the hypothalamus. Changes in GnRH release induce corresponding changes in luteinising hormone secretion which are responsible for the alternating presence or absence of ovulation in the female, and varying sperm production in the male. It is not yet known where and how this pineal indoleamine acts to exert this effect. Although melatonin binding sites are preferentially localised in the pars tuberalis (PT) of the adenohypophysis, the hypothalamus contains the physiological target sites of melatonin for its action on reproduction. Melatonin does not seem to act directly on GnRH neurons; rather it appears to involve a complex neural circuit of interneurons that includes at least dopaminergic, serotoninergic and excitatory aminoacidergic neurons.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0926-5287
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
355-66
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10420438-Animals, pubmed-meshheading:10420438-Cricetinae, pubmed-meshheading:10420438-Estrus, pubmed-meshheading:10420438-Female, pubmed-meshheading:10420438-Gonadotropin-Releasing Hormone, pubmed-meshheading:10420438-Gonads, pubmed-meshheading:10420438-Hypothalamo-Hypophyseal System, pubmed-meshheading:10420438-Interneurons, pubmed-meshheading:10420438-Luteinizing Hormone, pubmed-meshheading:10420438-Male, pubmed-meshheading:10420438-Melatonin, pubmed-meshheading:10420438-Neurotransmitter Agents, pubmed-meshheading:10420438-Photoperiod, pubmed-meshheading:10420438-Pineal Gland, pubmed-meshheading:10420438-Pituitary Gland, Anterior, pubmed-meshheading:10420438-Receptors, Cell Surface, pubmed-meshheading:10420438-Receptors, Cytoplasmic and Nuclear, pubmed-meshheading:10420438-Receptors, Melatonin, pubmed-meshheading:10420438-Reproduction, pubmed-meshheading:10420438-Rodentia, pubmed-meshheading:10420438-Seasons, pubmed-meshheading:10420438-Secretory Rate, pubmed-meshheading:10420438-Sheep, pubmed-meshheading:10420438-Species Specificity
pubmed:articleTitle
Melatonin and the seasonal control of reproduction.
pubmed:affiliation
Laboratoire de neuroendocrinologie sexuelle, Inra, PRMD, URA CNRS 1291, France. malpaux@tours.inra.fr
pubmed:publicationType
Journal Article, Review