Accumulation of radioiodine in thiouracil-hyperplastic thyroids of chicks.
Kinetics of accumulation of radioiodine was studied in thyroids of chickens before, during, and following ingestion of 0.25% thiouracil (TU). After a latent period of about 5 days, weight of the thyroid gland increased, reaching its maximum (42 mg/100 g body wt) after 21 days of TU ingestion; thyroid weight decreased immediately on withdrawal of TU but tended to plateau at a higher level than that of controls. One-way clearance increased by day 4 of ingestion of TU and reached its peak early during hyperplasia; it very quickly reverted to a control level on withdrawal of TU. Exit-rate constant increased markedly during early hyperplasia and decreased to a level less than normal after withdrawal of TU. Concentration of 127I decreased by a factor of 18 by 2 wk of feeding TU; it increased to practically a normal level by 1 wk after withdrawal of TU.
D000818:Animals; D006965:Hyperplasia; D007454:Iodides / Q000378:metabolism*; D007457:Iodine Radioisotopes; D007700:Kinetics; D013889:Thiouracil / Q000494:pharmacology; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology
D007454:Iodides; D007457:Iodine Radioisotopes; D013889:Thiouracil