{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T01:36:43Z","timestamp":1789349803837,"version":"build-2803163510"},"reference-count":0,"publisher":"Bioscientifica","issue":"3","content-domain":{"domain":["journals.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1989,3,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>We have investigated the effect of pinealectomy of ewes in pregnancy on the presence of the diurnal rhythm in fetal and maternal plasma concentrations of melatonin. Six ewes were pinealectomized between 104 and 118 days of gestation. Fetal and maternal blood samples were collected during 24-h periods between 125 and 140 days of gestation in the pinealectomized ewes and in an intact control (n = 4). There was a significant diurnal rhythm in both fetal and maternal plasma concentrations of melatonin in the control group. In this group, the fetal and maternal plasma melatonin concentrations were significantly higher in the dark (128\u00b74\u00b16\u00b72 and 192\u00b72\u00b1 10\u00b77 pmol\/l respectively) than in the light (46\u00b72 \u00b1 4\u00b72 and 25\u00b78 \u00b1 2\u00b71 pmol\/l respectively). However there was no diurnal rhythm in either the fetal or maternal plasma melatonin concentrations in the pinealectomized group between 125 and 140 days of gestation. In contrast to the control animals, there was also no light\u2013dark difference in the fetal or maternal plasma melatonin concentrations in four pinealectomized animals sampled frequently in the 3\u20137 days preceding delivery (mean length of gestation 146\u00b75 days). However, in the pinealectomized sheep there was a gradual increase in the combined light\u2013dark fetal plasma melatonin concentrations during late gestation from 27\u00b79 \u00b1 2\u00b78 pmol\/l (at 15\u201320 days before delivery) to 95\u00b72\u00b1 14\u00b71 pmol\/l on the day of delivery.<\/jats:p>\n                  <jats:p>We have therefore demonstrated that the maternal pineal is the major source of the diurnal rhythm in maternal and fetal plasma melatonin concentrations. However maternal pinealectomy does not appear to remove all the melatonin immunoreactivity from the maternal and fetal plasma in late gestation.<\/jats:p>\n                  <jats:p>Journal of Endocrinology (1989) 120, 459\u2013464<\/jats:p>","DOI":"10.1677\/joe.0.1200459","type":"journal-article","created":{"date-parts":[[2008,12,11]],"date-time":"2008-12-11T18:11:20Z","timestamp":1229019080000},"page":"459-464","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-5","source":"Crossref","is-referenced-by-count":55,"title":["Maternal pinealectomy abolishes the diurnal rhythm in plasma melatonin concentrations in the fetal sheep and pregnant ewe during late gestation"],"prefix":"10.1530","volume":"120","author":[{"given":"I. C.","family":"McMillen","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R.","family":"Nowak","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"416","container-title":["Journal of Endocrinology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/joe.bioscientifica.com\/view\/journals\/joe\/120\/3\/joe_120_3_013.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.bioscientifica.com\/joe\/article-pdf\/120\/3\/459\/98172\/joe_120_3_013.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/journals.bioscientifica.com\/joe\/article-pdf\/120\/3\/459\/98172\/joe_120_3_013.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T11:13:11Z","timestamp":1783595591000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.bioscientifica.com\/joe\/article\/120\/3\/459\/16351\/Maternal-pinealectomy-abolishes-the-diurnal-rhythm"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1989,3,1]]},"references-count":0,"journal-issue":{"issue":"3","published-print":{"date-parts":[[1989,3,1]]}},"URL":"https:\/\/doi.org\/10.1677\/joe.0.1200459","relation":{},"ISSN":["1479-6805","0022-0795"],"issn-type":[{"value":"1479-6805","type":"electronic"},{"value":"0022-0795","type":"print"}],"subject":[],"published":{"date-parts":[[1989,3,1]]}}}