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.

The effects of hypothyroidism and 2,4-dinitrophenol on growth hormone synthesis.

Abstract: After the administration of several agents which alter thyroid function, storage and synthesis of growth hormone (rGH) and storage of prolactin (rPRL) were studied in the rat pituitary gland. Hormone concentrations in pituitaries were measured by gel electrophoresis; synthesis was measured in pituitary glands incubated in vitro. The pituitary concentration of cyclic adenosine 3′,5′-monophosphate (cyclic AMP) and pituitary adenylate cyclase activity were also determined. In addition, serum thyroxin concentrations and binding of DL-thyroxin-2-14C by pituitary and hypothalamic tissues were measured. We obtained the following results. Hypothyroidism produced by propylthiouracil (PTU) reduced the synthesis of rGH 90-97% and that of rPRL 70-78% and resulted in a fall of 80% in pituitary concentrations of rGH and rPRL. These effects of PTU were reversed by the administration of thyroxin. Dinitrophenol (DNP) reduced serum thyroxin 25% and the concentrations of rGH and rPRL in the pituitary as well as their rates ...

Characteristics of agranulocytosis as an adverse effect of antithyroid drugs in the second or later course of treatment.

Abstract: Background: Agranulocytosis is a serious adverse effect of antithyroid drugs (ATDs) and mainly develops within three months after the start of uninterrupted ATD treatment. Agranulocytosis can also develop for the first time after interruption and subsequent resumption of the same ATD treatment. However, little is known with regard to agranulocytosis that develops after resumption of the same ATD treatment. Objectives: We investigated the characteristics of patients who developed agranulocytosis during their second or later course of ATD treatment. Methods: A total of 81 patients at our hospital were diagnosed with ATD-induced agranulocytosis. In 14 of the cases (methimazole (MMI), n=10; propylthiouracil (PTU), n=4), the agranulocytosis developed for the first time in the context of the second or later course of treatment with the same ATD; those patients were designated the “resumed group.” The 35 patients (MMI, n=28; PTU, n=7) who developed agranulocytosis during their first uninterrupted course of ATD t...

Stimulatory and inhibitory action of estradiol on TSH secretion.

Abstract: Subcutaneous administration of low doses of estradiol benzoate (EB: 0.004, 0.016, 0.064, 0.256 txg daily, 9–11 days) to rats ovariectomized for 28–30 days resulted in stimulation or inhibition of pituitary-thyroid function. The relatively low dose of 0.064 /xg elevated pituitary and plasma TSH levels and induced thyroid hyperplasia. A higher dose level (.256 μg) inhibited TSH secretion by the pituitary and caused involution of the thyroid gland. The biphasic action of estradiol of TSH secretion was not attributable to alterations in the thyroxine (T4) binding capacity of the blood proteins. Resin uptake of radiothyroxine from plasma was significantly decreased in rats treated with propylthiouracil (PTU) or in animals subjected to thyroidectomy, ovariectomy and hypothalamic lesioning. The administration of EB to hypothyroid rats failed to influence appreciably T4 resin uptake from plasma. In contrast, a critical dose level of EB (.02 μg daily, 7–8 days) stimulated TSH secretion in thyroidectomized, ovariec...

Thyroid function in the rat during pregnancy and lactation.

Abstract: 1) Pregnant rats were fed 0.15% propylthiouracil (PTU) from the 10th to the 19th day of pregnancy and 1, 2, 3, 4 or 5 μg. T4 were injected daily during this time. The regression slopes of the thyroid weights were similar to those of the corresponding controls except that 2 μg. T4 produced less decrease in thyroid size in pregnant than in non-pregnant rats. 2) Pregnant rats were fed a low-iodine diet from the 10th to the 19th day of pregnancy and doses of T4 were administered during this interval as in 1). The regression slopes of the thyroidal I131 uptake of the pregnant and non-pregnant rats were identical but uptakes were consistently slightly lower at each point for the pregnant rats. 3) Following seven days of low-iodine diet, thyroidal I131 uptakes were determined at one to two day intervals from the 8th day of gestation to the 29th day of lactation. Uptakes were not statistically different from the controls until the 20th day of pregnancy when a marked drop of approximately 50% occurred which persis...

Propylthiouracil (PTU)-Induced Agranulocytosis Treated with Recombinant Human Granulocyte Colony-Stimulating Factor (G-CSF)

Abstract: Two premenopausal female patients with Graves' hyperthyroidism and propylthiouracil (PTU)-induced agranulocytosis are presented. The first patient, age 47, received 300 mg of PTU per day and developed agranulocytosis within 6 weeks of the commencement of therapy. There were no granulocytes in the peripheral smear and a bone marrow biopsy demonstrated an absence of the entire myeloid cell line as well as the presence of many granulomas. The second patient, age 39, received PTU 1600 mg per day for two and half weeks and then 2 days of methimazole, 200 mg per day. She developed complete agranulocytosis on peripheral smear within 3 weeks of the initiation of therapy. Her bone marrow biopsy demonstrated maturation arrest of the granulocytic cell line at the myelocyte stage. In addition to discontinuing their antithyroid drugs, both patients were treated with G-CSF subcutaneously. The first patient received 300 micrograms of G-CSF on days 2 and 4 after discontinuing PTU with the appearance of 4.7 x 10(9)/L granulocytes and granulocyte precursors on day 4. The second patient received 575 micrograms of G-CSF for 2 days and 300 micrograms for 1 additional day beginning on the third day after discontinuing antithyroid drugs. On the second treatment day there were 5.8 x 10(9)/L granulocytes and granulocyte precursors on the peripheral smear. A comparison to previously published cases on antithyroid drug induced agranulocytosis suggests that the use of G-CSF decreased the amount of time required for marrow recovery after the cessation of the offending drug.