{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T19:36:50Z","timestamp":1781638610784,"version":"3.54.5"},"reference-count":0,"publisher":"Oxford University Press (OUP)","issue":"2","content-domain":{"domain":["eje.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1981,6]]},"abstract":"<jats:title>Abstract.<\/jats:title>\n<jats:p>The effect of epinephrine (E) and 5-hydroxytryptamine (5-HT) on some elements involved in thyroid iodine organification was studied using a bovine thyroid subcellular fraction sedimented at 30 000 <jats:italic>g<\/jats:italic>. <jats:sup>131<\/jats:sup>I-incorporation into particulate proteins and into tyrosine was increased by 10<jats:sup>\u22123<\/jats:sup> <jats:sc>m<\/jats:sc> and 10<jats:sup>\u22125<\/jats:sup> <jats:sc>m<\/jats:sc> E and 5-HT. This effect was inhibited by 6-n-propyl-2-thiouracil and by catalase.<\/jats:p>\n<jats:p>In the presence of these amines the activity of NADPH-cytochrome c reductase was not modified. Both E and 5-HT were able to generate H<jats:sub>2<\/jats:sub>O<jats:sub>2<\/jats:sub> when added to the particulate fraction as measured by the oxidation of o-dianisidine. H<jats:sub>2<\/jats:sub>O<jats:sub>2<\/jats:sub> generation and [<jats:sup>131<\/jats:sup>I]iodotyrosine formation were inhibited by pargyline, a monoamine oxidase (MAO) inhibitor. Tyramine, a specific substrate for thyroid MAO, produced H<jats:sub>2<\/jats:sub>O<jats:sub>2<\/jats:sub> and increased [<jats:sup>131<\/jats:sup>I]iodotyrosine formation. This effect was higher when compared to the effect elicited by E or 5-HT. The stimulatory effects of tyramine were blocked by pargyline. The action of tyramine on H<jats:sub>2<\/jats:sub>O<jats:sub>2<\/jats:sub> generation and [<jats:sup>131<\/jats:sup>I]iodotyrosine formation was diminished when E or 5-HT were incorporated to the system.<\/jats:p>\n<jats:p>From these results it is suggested that E and 5-HT serving as MAO substrates would generate H<jats:sub>2<\/jats:sub>O<jats:sub>2<\/jats:sub> and in this way increase the thyroid iodine organification. On the other hand, these amines would be able to reduce the increased H<jats:sub>2<\/jats:sub>O<jats:sub>2<\/jats:sub> generation induced by tyramine and thus decrease the iodination process. These findings could explain the stimulatory or inhibitory effects of biogenic amines on thyroid function which are dependent on the previous thyroid activity.<\/jats:p>","DOI":"10.1530\/acta.0.0970207","type":"journal-article","created":{"date-parts":[[2008,12,15]],"date-time":"2008-12-15T21:36:12Z","timestamp":1229376972000},"page":"207-212","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-1","source":"Crossref","is-referenced-by-count":2,"title":["Effect of epinephrine and 5-hydroxytryptamine on in vitro thyroid iodine organification"],"prefix":"10.1093","volume":"97","author":[{"given":"Ana Mar\u00eda","family":"Masini-Repiso","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aldo H\u00e9ctor","family":"Coleoni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","container-title":["Acta Endocrinologica"],"original-title":[],"link":[{"URL":"https:\/\/eje.bioscientifica.com\/view\/journals\/eje\/97\/2\/acta_97_2_010.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/eje.bioscientifica.com\/view\/journals\/eje\/97\/2\/acta_97_2_010.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,2,14]],"date-time":"2023-02-14T16:11:08Z","timestamp":1676391068000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/ejendo\/article\/97\/2\/207\/6804066"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1981,6]]},"references-count":0,"journal-issue":{"issue":"2"},"URL":"https:\/\/doi.org\/10.1530\/acta.0.0970207","relation":{},"ISSN":["0804-4643","1479-683X"],"issn-type":[{"value":"0804-4643","type":"print"},{"value":"1479-683X","type":"electronic"}],"subject":[],"published":{"date-parts":[[1981,6]]}}}