Thyroidal Metabolism of Diiodotyrosine

Slingerland, D. Ward; Josephs, Roma K.

doi:10.1210/endo-62-6-853

Cited by 8 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A third possibility is that both enzyme systems may be independently influenced by TSH. Michel states that TSH in vivo enhances thyroidal deiodinase (37); however, such an effect was not observed during a 24-hour incubation in vitro (38). The data presented here do not allow discrimination of these possibilities, and clarification of this TSH-induced response must await further in vitro study.…”

Section: Discussionmentioning

confidence: 60%

In Vitro Thyrotropin-Induced Proteolysis in the Thyroid Gland*

Poffenbarger¹,

Powell²,

Deiss³

1963

J. Clin. Invest.

View full text Add to dashboard Cite

Numerous studies, both in vivo and in vitro, have been designed to define the biochemical events influenced by the action of thyrotropin (TSH) on the thyroid gland. In vivo experiments have shown that this hormone stimulates growth of the follicular epithelium, trapping of inorganic iodide, biosynthesis of hormonal iodine, turnover of thyroglobulin, and release of inorganic iodide and hormonal iodine. The latter action has received much attention because of its relevance to the concentration of circulating thyroid hormone and because of the promptness of this response in vivo. De Robertis demonstrated an increase in intrafollicular proteolytic activity after administration of TSH to rats (1). Keating, Rawson, Peacock, and Evans (2) noted loss of radioiodine from the chick thyroid after TSH administration. Similar results have been observed in other laboratory animals (3, 4). The administration of TSH to euthyroid humans also results in prompt release of radioiodine from the thyroid (5-7), occurring 90 minutes after intramuscular inj ection in one study (7).In vitro techniques have permitted investigation in a more rigidly controlled environment. Such observations on the effect of TSH added to thyroid tissue have confirmed the stimulus to the trapping of iodide (8, 9). TSH in vitro has also been shown to enhance certain parameters of intermediary metabolism such as carbon-1 oxidation of glucose (10, 11), phospholipid synthesis (12), oxygen consumption, lipogenesis from labeled glucose, incorporation of inositol into phospholipid (13), and the level of triphosphopyridine nucleotide (14). Few

show abstract