Abstract
1. Thyrotropic hormone (TSH) enhanced the process of the conversion of iodide to protein-bound iodine when pig thyroid slices were incubated with TSH for a short period. It was proved that TSH-sensitive reaction was iodination of thyroglobulin.
2. Specificity of this reaction was con-firmed since three different preparations showed the same effect and serum albumin or ACTH had no effect.
3. The extent of the conversion of iodide to protein-bound iodine was proportional to the logarithm of TSH concentration, though the slope of the dose-response curve conside-rably varied with glands from which slices were prepared.
4. Anti-thyroid compounds and other reagents affected the iodine transfer and the TSH effect in various manners.
The author wishes to express his sincere thanks to Prof. N. Ui for his guidance and encouragement during this work. The expense of this study was defrayed in part by a grant from the Ministry of Education.
