Propylthiouracil

About: Propylthiouracil is a research topic. Over the lifetime, 2181 publications have been published within this topic receiving 46996 citations. The topic is also known as: Thyreostat® & 2,3-dihydro-6-propyl-2-thioxo-4(1H)-pyrimidinone.

Thyroidal content of thyrocalcitonin in hypothyroid and hyperthyroid rats.

Abstract: The thyrocalcitonin content of the thyroid glands of euthyroid, hyperthyroid and hypothyroid rats fed a calcium deficient diet was determined in 2 separate experiments by bioassay. Hyperthyroidism was produced by the injection of 50 μg l-thyroxine or 200 mU thyrotropin per day, and hypothyroidism by the dietary administration of 0.05% propylthiouracil or an iodine deficient diet. The log-dose response curve for the hypocalcemic activity of the thyroid homogenates from the euthyroid rats was linear between 0.24 and 0.96 mg thyroid tissue, equivalent to 0.018–0.072 of a single rat thyroid gland. No significant differences in the hypocalcemic response of assay rats was observed when a comparison was made of thyroid tissue homogenates that included parathyroid tissue and thyroid homogenates in which the parathyroid gland was removed prior to tissue homogenization. Thyroxine consistently caused a significant 27–35% reduction in the thyroidal content of thyrocalcitonin, whereas the administration of thyrotropin...

Effects of thyroxine on cell proliferation in human multinodular goiter: a study on growth of thyroid tissue transplanted to nude mice.

Abstract: To analyze the inhibitory effect of thyroxine (T4) on thyroid growth, freshly obtained biopsies of human nontoxic multinodular goiter tissue from 9 patients were transplanted to nude mice. After the implantation period, thyroid growth was stimulated by either hemithyroidectomy (HT) or by administration of the goitrogen propylthiouracil (PTU), with or without simultaneous administration of T4. During the latter period,3H-thymidine was continuously administered by osmotic minipumps to label replicating cells. After processing of the tissue for autoradiography, the fraction of labeled cells (LI) was calculated. Following HT, the fraction of labeled cells in nontoxic multinodular goiter tissue was 4.8%. T4 significantly reduced the LI to 1.0%. The goitrogen induced transplant growth, the LI varying between 28% and 61% in the different specimens. Administration of T4 resulted in lower LI in all transplants: in 5 specimens the LI was similar to control transplants. In transplants from 3 goiter specimens, however, significantly higher LI were found. The present results show that administration of T4 significantly inhibits growth of human thyroid tissue. The effect seems, however, to vary in different specimens of nontoxic goiter, indicating a varying degree of autonomous replicating activity.

Effects of Thyroid Dysfunction on Reproductive Hormones in Female Rats.

Abstract: Thyroid hormones (THs) play a critical role in the development of ovarian cells. Although the effects of THs on female reproduction are of great interest, the mechanism remains unclear. We investigated the effects of TH dysregulation on reproductive hormones in rats. Propylthiouracil (PTU) and L-thyroxine were administered to rats to induce hypo- and hyperthyroidism, respectively, and the reproductive hormone profiles were analyzed by radioimmunoassay (RIA). Ovarian histology was evaluated with hematoxylin and eosin (HE however, the serum testosterone (T) level was increased only in hypothyroid rats at day 21. In addition, the expression levels of FSH receptor, cholesterol side-chain cleavage enzyme (P450scc), and steroidogenic acute regulatory protein (StAR) were decreased in both rat models. Moreover, the onset of puberty was significantly delayed in the hypothyroid group. These results provide evidence that TH dysregulation alters reproductive hormone profiles, and that the initiation of the estrous cycle is postponed in hypothyroidism.

Lupus erythematosus-like syndrome induced by thiamazole and propylthiouracil.

Abstract: A 17-year-old Japanese woman developed a lupus erythematosus-like syndrome during treatment for Graves' disease with thiamazole and propylthiouracil. Erythema, arthralgia, and low grade fever developed during therapy with thiamazole; purplish-red erythema developed during therapy with propylthiouracil. Antinuclear antibodies, anti-single-stranded DNA antibodies, and anti-double-stranded DNA antibodies were positive throughout the administration of these two drugs. Eruptions and other symptoms improved after their discontinuation. The titers of autoantibodies also decreased two months after withdrawal. The patient had HLA DR4.