{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T03:55:27Z","timestamp":1785902127063,"version":"3.56.0"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"24","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1985,12]]},"abstract":"<jats:p>FRTL-5 rat thyroid cells grown and maintained in a medium containing 0.05 nM thyrotropin have a 10-fold higher number of alpha 1-adrenergic receptors on their cell surface than FRTL-5 cells maintained in the absence of thyrotropin in their medium. The increased number of alpha 1-adrenergic receptors, measured as increased specific [3H]prazosin binding per microgram of DNA, is not associated with any changes in Kd values for prazosin. Thyrotropin increases the number of alpha 1-adrenergic receptors by inducing their biosynthesis, as evidence by the inhibitory effects of cycloheximide or actinomycin D; the effect on biosynthesis is cAMP-mediated, since 8-bromoadenosine 3',5'-cyclic monophosphate, cholera toxin, forskolin, or 3-isobutyl-1-methylxanthine can mimic the thyrotropin effect in both extent and time course. The alpha 1-adrenergic receptors on FRTL-5 thyroid cells have been functionally linked to iodide efflux into the follicular lumen and to the iodination of thyroglobulin--i.e., to the formation of thyroid hormones; the alpha 1-adrenergic receptor signal is mediated by Ca2+ rather than by cAMP and involves arachidonic acid intermediates. The present data thus describe a unique upregulation phenomenon wherein the sequential expression of two receptors (thyrotropin and alpha 1-adrenergic) and two distinct signal systems (cAMP and Ca2+) are apparently a necessary prelude to thyroid hormone homoeostasis.<\/jats:p>","DOI":"10.1073\/pnas.82.24.8677","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T05:50:52Z","timestamp":1149054652000},"page":"8677-8680","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":17,"title":["Thyrotropin upregulates alpha 1-adrenergic receptors in rat FRTL-5 thyroid cells."],"prefix":"10.1073","volume":"82","author":[{"given":"D","family":"Corda","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L D","family":"Kohn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1985,12]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.82.24.8677","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T12:23:43Z","timestamp":1649852623000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.82.24.8677"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1985,12]]},"references-count":0,"journal-issue":{"issue":"24","published-print":{"date-parts":[[1985,12]]}},"alternative-id":["10.1073\/pnas.82.24.8677"],"URL":"https:\/\/doi.org\/10.1073\/pnas.82.24.8677","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1985,12]]},"assertion":[{"value":"1985-12-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}