Showing papers on "Propylthiouracil published in 1970"
TL;DR: Thirty-eight patients aged 2 to 18 years with hyperthyroidism were followed with hematologic studies while receiving propylthiouracil and ten had one or more episodes of leukopenia.
108 citations
TL;DR: The physiological potencies of l-thyroxine and l-triiodothyroxine are equal in propylthiouracil (PTU)-fed radiothyroidectomized (RT) chicks and Liver hypertrophy and liver glycogen accumulation are distinct criteria of hypothyroidism in the chick and are restored to near normal levels by small daily doses of T4 or T3.
34 citations
TL;DR: It is concluded that thyroid autonomy and hyperfunction in Graves' disease are probably not due to circulating LATS, and the hypothesis is proposed that the primary abnormality is an intrinsic disorder of the thyroid gland, rendering it, to a varying degree, autonomous and hyperfunctional.
Abstract: The relationship between serum LATS concentration, measured in tenfold IgG concentrates, and thyroid function and size has been studied in 35 patients with untreated Graves' disease and in 27 patients during treatment with antithyroid drugs. There was no correlation between serum LATS activity and serum T 4 , free T 4 , T 3 resin uptake, thyroid 20-minute or 24-hour 131 I uptake or estimated thyroid weight. Nonsuppressibility of thyroid 20-minute 131 I uptake after administration of triiodothyronine (T 3 ) was similarly not correlated with serum LATS levels either before and during treatment. Dissociation between serum LATS and suppressibility occurred in both directions; there were five patients in whom thyroid uptake became suppressible despite persistence of LATS in serum, whereas in 15 instances nonsuppressibility of thyroid uptake continued when LATS was undetectable. Similarly, there was no correlation between serum LATS and thyroid nonsuppressibility when all tests in all 27 patients during treatment were analyzed. Serum TSH was often detectable when patients became euthyroid or hypothyroid during treatment. In these patients pre-T 3 thyroid 20-minute 131 I uptake did not regularly rise nor was it regularly suppressed after administration of T 3 , whereas serum TSH invariably fell sharply after T 3 . When serum LATS and serum TSH were simultaneously considered as determinants of the degree of suppressibility of 20-minute uptake by T 3 , there was no effect of LATS whatsoever, but a trend toward an effect of TSH, albeit not statistically significant. It is concluded that thyroid autonomy and hyperfunction in Graves' disease are probably not due to circulating LATS. The hypothesis is proposed that the primary abnormality is an intrinsic disorder of the thyroid gland, rendering it, to a varying degree, autonomous and hyperfunctional.
30 citations
TL;DR: It is suggested that the changes in plasma insulin found in the thyroidectomized rats might be related to the impairment of the function of the pituitaries and of pituitary-dependent glands which accompanies hypothyroidism.
Abstract: We have found that the plasma insulin level of normal-growing rats increases with time, and is positively correlated to their body weight. On the contrary, the body weight and plasma insulin of thyroidectomized rats stopped increasing at about 13–15 days after the operation and from then onward remained lower than for age-paired controls. The variability of the individual plasma insulin values around their group means was significantly smaller than that of the age-paired controls. Very small daily doses of L-thyroxine (0.2 µg/100 g body wt), which reinitiated growth in thyroidectomized rats, increased their plasma insulin level and its variability toward the values of agepaired controls. It is suggested that the changes in plasma insulin found in the thyroidectomized rats might be related to the impairment of the function of the pituitary and of pituitary-dependent glands which accompanies hypothyroidism. The changes in the plasma insulin levels of rats on a low iodine intake and C1O4-, ReO4- and, probabl...
28 citations
TL;DR: Treatment with thyroxin neonatally, after prenatal PTU administration, prevented the late pituitary-thyroidal changes but not the gonadal effects, and the possibility that pregnant women receiving PTU during pregnancy may have children with mild late gonadal and thyroidal alterations must be considered.
27 citations
TL;DR: Most of the labeled cellswere chromophobic without the morphological characteristics ofthyroidectomy cells, suggesting that they arose from potentially thyrotropic cells, not involved at that time in the hypersecretion of TSH.
Abstract: Mature male rats weighing 190–230 g were treated for 3–24 days with 2.5 mg of propylthiouracil (PTU) ip every 12 hr. During the last 48 hr of this treatment they were injected with 4 doses of tritiated thymidine (0.5 µCi per g body weight per dose). Periodic acid- Schiff(PAS)-stained sections of their pituitary glands were then subjected to autoradiography. A 3-foldincr ase in labeling index and a 6-fold increase in mitotic index was found after 15 days of treatmentwith PTU. Most of the labeled cellswere chromophobic without the morphological characteristics ofthyroidectomy cells, suggesting that they arose from potentially thyrotropic cells, not involved at that time in the hypersecretion of TSH. (Endocrinology 87: 1113,1970)
20 citations
TL;DR: Effects of endogenous and exogenous TSH on rabbit thyroid cell membrane properties were studied and the addition of TSH to the perfusate produced a rapid fall in resistance and an increase in capacitance across the follicular wall.
Abstract: Effects of endogenous and exogenous TSH on rabbit thyroid cell membrane properties were studied. Both propylthiouracil (PTU) pretreatment and acute cold stress produced a fall in transmembrane potentials. PTU pretreated rabbit follicles had higher capacitances and lower resistances across their walls than follicles from control rabbits. This can be explained on the basis of increased membrane area. PTU pretreated animals also had a lower luminal electrical potential. In perfused glands in vitro, the addition of TSH to the perfusate produced a rapid fall in resistance and an increase in capacitance across the follicular wall. These changes are attributed to an increase in membrane area and to a fall in specific membrane resistance. (Endocrinology 86: 1154, 1970)
16 citations
TL;DR: The administration of the thyrotrophic hormone (TSH) significantly increased the uptake of 32P by the testes of previously untreated 5-day-old chicks, and estimated levels of FSH and LH contamination were low enough to suggest that the TSH itself may have possessed some gonadotrophic properties.
11 citations
TL;DR: It appears that the fall in ATP after iodide injection is related to the transport, but not to the organification, step of the thyroidal iodine metabolism and that the parallel decrease in thyroidal ATP occurred as early as 5 min and lasted at least 60 min after injection of 250 μg of iodide.
Abstract: Adenosine-5′-triphosphate (ATP) and pyridine nucleotides (PN) have been measured in thyroids of normal rats 30 min after injection of 25 or 250 μg of iodide. A significant decrease in thyroidal ATP occurred as early as 5 min and lasted at least 60 min after injection of 250 μg of iodide. A larger response was induced by 250 than by 25 μg of iodide. When measured at 30 min, thyroidal PN were also decreased by iodide injection. Iodide had no effect on the ATP or PN content of the liver. The effects of iodide on ATP concentrations in the thyroids of hypophysectomized rats were similar to those seen in intact rats; its effects on PN concentration were not measured. The response of both ATP and PN concentrations could be prevented by injection of sodium perchlorate or sodium thiocyanate, but not by propylthiouracil. It appears, therefore, that the fall in ATP after iodide injection is related to the transport, but not to the organification, step of the thyroidal iodine metabolism and that the parallel decrease...
7 citations
TL;DR: The results suggest that the thyroid gland influences significantly the acetylcholine-ChE system of the mature brain.
5 citations
TL;DR: It is suggested that the psammoma bodies may contain a major part of the iodine which has a long biologic half-life in the thyroids of chronically iodine-deficient rats.
Abstract: Radioiodine concentration in or around psammoma bodies in the thyroids of rats fed an iodine-deficient diet for several months has been demonstrated by radioautography. Radioactivity appears in the psammoma bodies within 5 min after intravenous injection of radioiodine. The radioactivity in the psammoma bodies does not disappear during 24 days’ treatment with propylthiouracil and perchlorate even though most of the radioactivity is lost from the remaining thyroid tissue. It is suggested that the psammoma bodies may contain a major part of the iodine which has a long biologic half-life in the thyroids of chronically iodine-deficient rats. (Endocrinology 87: 245, 1970)
TL;DR: It is suggested that the lack of a specific thyroidal compound binding protein, which is known to be one of the principal differences between mammalian and avian sera, may be the cause of this phenomenon.
01 Jan 1970
TL;DR: The thyroid would seem to influence mammogenesis by its general metabolic effect (Jacobsohn, 1958, 1959); a certain degree of hypothyroidism enhances alveolar development in the rat, but it has an inhibitory effect on mammogenesis in the mouse.
Abstract: The thyroid would seem to influence mammogenesis by its general metabolic effect (Jacobsohn, 1958, 1959). A certain degree of hypothyroidism enhances alveolar development in the rat, but it has an inhibitory effect on mammogenesis in the mouse (Folley, 1956). Treating rats with propylthiouracil (an antithyroid drug) stimulates mammary growth (Ben-David, Dikstein and Sulman, 1966). Mammogenesis can be elicited in the hypophysectomized-adrenalectomizedthyroidectomized rat by giving ovarian hormones + prolactin, STH and hydrocortisone, without the addition of thyroid hormones (Chen, Johnson, Lyons, Li and Cole, 1955).