This Article Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints, Permissions and Rights Citing Articles Citing Articles via Google Scholar Google Scholar Articles by SINGH, V.N. Articles by CHAIKOFF, I.L. Search for Related Content PubMed PubMed Citation Articles by SINGH, V.N. Articles by CHAIKOFF, I.L.

Effects of l-Methyl-2-mercaptoimidazole and Perchlorate on the Insulin-Mediated Enhancement of ¹³¹I Incorporation Into Iodoamino Acids by Fetal Thyroid Glands in Organ Culture

Department of Physiology, University of California Berkeley, California

This investigation was supported by a grant from the USPHS.

Abstract

The effect of insulin was studied on ¹³¹I uptake and its corporation into protein-bound MIT, DIT and T₄ by thyroid glands excised from fetuses of 20- or 21-daypregnant rats and cultured for 3 days. Insulin enhanced the incorporation of ¹³¹I into protein- bound MIT and DIT. Labeled thyroxine was not detected in the explants 6 hr after the addition of ¹³¹I to the basal medium, but did appear when insulin was added to the medium. Insulin also enhanced the ¹³¹I uptake and its incorporation into iodoamino acids by glands that were pretreated with sodium perchlorate so as to destroy their iodide-concentrating ability. However, insulin did not alter the ¹³¹I iodide recoveries in the glands pretreated with Tapazole. It is suggested that insulin increased the incorporation of ¹³¹I into protein-bound iodotyrosines and thyroxine by stimulating some step or steps subsequent to iodide transport. (Endocrinology 78: 339, 1966)

Received July 26, 1965.