{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T14:20:08Z","timestamp":1784557208568,"version":"3.55.0"},"reference-count":0,"publisher":"Bioscientifica","issue":"3","content-domain":{"domain":["joe.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2008,3]]},"abstract":"<jats:p>\n                    In this study, we tried to elucidate the changes in thyroid hormone (TH) receptor \u03b22 (TR\u03b22) expression at the different levels of the hypothalamo\u2013pituitary\u2013thyroidal (HPT) axis during the last week of chicken embryonic development and hatching, a period characterized by an augmented activity of the HPT axis. We quantified TR\u03b22 mRNA in retina, pineal gland, and the major control levels of the HPT axis \u2013 brain, pituitary, and thyroid gland \u2013 at day 18 of incubation, and found the most abundant mRNA content in retina and pituitary. Thyroidal TR\u03b22 mRNA content increased dramatically between embryonic day 14 and 1 day post-hatch. In pituitary and hypothalamus, TR\u03b22 mRNA expression rose gradually, in parallel with increases in plasma thyroxine concentrations. Using\n                    <jats:italic>in situ<\/jats:italic>\n                    hybridization, we have demonstrated the presence of TR\u03b22 mRNA throughout the diencephalon and confirmed the elevation in TR\u03b22 mRNA expression in the hypophyseal thyrotropes.\n                    <jats:italic>In vitro<\/jats:italic>\n                    incubation with THs caused a down-regulation of TR\u03b22 mRNA levels in embryonic but not in post-hatch pituitaries. The observed expression patterns in pituitary and diencephalon may point to substantial changes in TR\u03b22-mediated TH feedback active during the perinatal period. The strong rise in thyroidal TR\u03b22 mRNA content could be indicative of an augmented modulation of thyroid development and\/or function by THs toward and after hatching. Finally, THs proved to exert an age-dependent effect on pituitary TR\u03b22 mRNA expression.\n                  <\/jats:p>","DOI":"10.1677\/joe-07-0443","type":"journal-article","created":{"date-parts":[[2008,2,29]],"date-time":"2008-02-29T13:52:07Z","timestamp":1204293127000},"page":"519-528","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-5","source":"Crossref","is-referenced-by-count":17,"title":["Thyroid hormone receptor \u03b22 is strongly up-regulated at all levels of the hypothalamo\u2013pituitary\u2013thyroidal axis during late embryogenesis in chicken"],"prefix":"10.1530","volume":"196","author":[{"given":"Sylvia V H","family":"Grommen","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lutgarde","family":"Arckens","sequence":"additional","affiliation":[{"name":"Research Group of Comparative EndocrinologyAnimal Physiology and Neurobiology Section, Department of Biology, K U Leuven, Naamsestraat 61, B-3000 Leuven, Belgium1Research Group of Neuroplasticity and NeuroproteomicsAnimal Physiology and Neurobiology Section, Department of Biology, K U Leuven, Naamsestraat 59, B-3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tim","family":"Theuwissen","sequence":"additional","affiliation":[{"name":"Research Group of Comparative EndocrinologyAnimal Physiology and Neurobiology Section, Department of Biology, K U Leuven, Naamsestraat 61, B-3000 Leuven, Belgium1Research Group of Neuroplasticity and NeuroproteomicsAnimal Physiology and Neurobiology Section, Department of Biology, K U Leuven, Naamsestraat 59, B-3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Veerle M","family":"Darras","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bert","family":"De Groef","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"416","container-title":["Journal of Endocrinology"],"original-title":[],"link":[{"URL":"https:\/\/joe.bioscientifica.com\/view\/journals\/joe\/196\/3\/519.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/joe.bioscientifica.com\/downloadpdf\/journals\/joe\/196\/3\/519.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T13:53:24Z","timestamp":1784555604000},"score":1,"resource":{"primary":{"URL":"http:\/\/journals.bioscientifica.com\/joe\/article\/196\/3\/519-528\/21582"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2007,12,19]]},"references-count":0,"journal-issue":{"issue":"3"},"URL":"https:\/\/doi.org\/10.1677\/joe-07-0443","relation":{},"ISSN":["0022-0795","1479-6805"],"issn-type":[{"value":"0022-0795","type":"print"},{"value":"1479-6805","type":"electronic"}],"subject":[],"published":{"date-parts":[[2007,12,19]]}}}