Ultrastructure of thyroid glands transplanted into the anterior eye chamber of thyroidectomized rats

Deep cervical fascia forms a connective tissue sheath around the thyroid gland. Delicate trabeculae and septa penetrate the gland indistinctly dividing the gland into lobes and lobules which in turn composed of follicles.1,2,3 These follicles are structural units of thyroid gland which varies greatly in size and shape.4 The number of follicles varies in different age groups. The study was carried out to see the percentage of area occupied by follicles in the stained section of thyroid glands in different age groups. The collected samples were grouped as A (3.5 20yrs), B (21- 40yrs) & C (41 78yrs). Percentage of area occupied by follicles was (58.55±10.72) in group A, (63.79±12.35) in group B + (63.39±8.29) in group C.DOI: http://dx.doi.org/10.3329/updcj.v1i2.13981 Update Dent. Coll. j. 2011: 1(2): 17-20

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EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

Acta Endocrinologica ◽

10.1530/acta.0.0770064 ◽

1974 ◽

Vol 77 (1) ◽

pp. 64-70 ◽

Cited By ~ 9

Author(s):

Gustav Wägar

Keyword(s):

Protein Synthesis ◽

Actinomycin D ◽

The Other ◽

Leucine Incorporation ◽

Short Term ◽

Other Hand ◽

Thyroid Glands ◽

Translational Level ◽

Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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INHIBITION OF THYROGLOBULIN BIOSYNTHESIS AND DEGRADATION BY EXCESS IODIDE. SYNERGISM WITH LITHIUM

Acta Endocrinologica ◽

10.1530/acta.0.0810495 ◽

1976 ◽

Vol 81 (2) ◽

pp. 495-506 ◽

Cited By ~ 9

Author(s):

A. Radvila ◽

R. Roost ◽

H. Bürgi ◽

H. Kohler ◽

H. Studer

Keyword(s):

Protein Synthesis ◽

Thyroid Gland ◽

Inhibitory Action ◽

Inhibit Protein Synthesis ◽

Thyrotrophic Hormone ◽

Thyroid Glands ◽

Pre Treatment ◽

Excess Iodide ◽

Kidney Liver

ABSTRACT Lithium and excess iodide inhibit the release of thyroid hormone from preformed stores. We thus tested the hypothesis that this was due to an inhibition of thyroglobulin breakdown. Rats were pre-treated with propylthiouracil (PTU) for 3 weeks in order to deplete their thyroids of thyroglobulin. While the PTU was continued, lithium chloride (0.25 mEq./100 g weight) or potassium iodide (3 mg per rat) were injected every 12 h for 3 days. Thereafter the thyroglobulin content in thyroid gland homogenates was measured. PTU pre-treatment lowered the thyroglobulin content from 4.21 to 0.22 mg/100 mg gland. Lithium caused a marked re-accumulation of thyroglobulin to 0.60 mg/100 mg within 3 days. While iodide alone had only a borderline effect, it markedly potentiated the action of lithium and a combination of the two drugs increased the thyroglobulin content to 1.04 mg/100 mg. Thyroxine was injected into similarly pre-treated animals to suppress secretion of thyrotrophic hormone. This markedly inhibited the proteolysis of thyroglobulin and 1.3 mg/100 mg gland accumulated after 3 days. Excess iodide, given in addition to thyroxine, decreased the amount of thyroglobulin accumulated to 0.75 mg/100 mg gland. To study whether this could be explained by an inhibitory action of iodide on thyroglobulin biosynthesis, thyroid glands from animals treated with excess iodide were incubated in vitro in the presence of 0.2 mm iodide for 3 h. Iodide decreased the incorporation of radioactive leucine into total thyroidal protein and into thyroglobulin by 25 and 35 % respectively. Iodide did not inhibit protein synthesis in the kidney, liver or muscle tissue. Thus, large doses of iodide selectively inhibit thyroglobulin biosynthesis.

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Isolation of a FGF-like growth factor from porcine thyroid glands

Acta Endocrinologica ◽

10.1530/acta.0.120s147 ◽

1989 ◽

Vol 120 (3_Suppl) ◽

pp. S147-S148

Author(s):

G. BECHTNER ◽

B. RIEDER ◽

U. LINSENMAIER ◽

W. GREIL ◽

R. GÄRTNER

Keyword(s):

Growth Factor ◽

Thyroid Glands

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The functional state of the parathyroid glands among patients with autoimmune thyroiditis with the presence of calcifications in the thyroid glands

Endocrine Abstracts ◽

10.1530/endoabs.70.ep532 ◽

2020 ◽

Author(s):

Emma Badalyan ◽

Maria Badalyan

Keyword(s):

Functional State ◽

Autoimmune Thyroiditis ◽

Parathyroid Glands ◽

Thyroid Glands

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EFFECT OF EXPERIMENTALLY INDUCED THYROIDITIS ON BIOSYNTHESIS OF THYROXINE IN RATS

Acta Endocrinologica ◽

10.1530/acta.0.0620011 ◽

1969 ◽

Vol 62 (1) ◽

pp. 11-20 ◽

Cited By ~ 1

Author(s):

Colum A. Gorman ◽

James W. Anderson ◽

Eunice V. Flock ◽

Charles A. Owen ◽

Khalil G. Wakim

Keyword(s):

Intravenous Administration ◽

Hashimoto's Thyroiditis ◽

Sprague Dawley ◽

Thyroid Extract ◽

Histologic Appearance ◽

Gland Weight ◽

Sprague Dawley Rats ◽

Thyroid Glands ◽

And Control ◽

Experimentally Induced

ABSTRACT Thyroiditis was induced in Sprague-Dawley rats by repeated immunization with thyroid extract and Freund's adjuvant. Immunized and control animals were killed at intervals up to 6 hours after intravenous administration of 131I as iodide at 5, 8 and 10 weeks after the first injection. Radioiodinated compounds in the thyroid glands were identified chromatographically. Evidence of moderate thyroiditis was present (histologic appearance, gland weight, and protein-bound iodine-butanol-extractable iodine difference) but the rate of incorporation of radioiodide into thyroxine, the percentage of radioactivity in the gland as iodide, and the MIT/DIT ratio were not significantly different in immunized and control animals. The MIT/DIT ratio was found to vary with time after 131I administration in both immunized and control animals. These studies did not uncover a defect in organification of iodide in experimental thyroiditis similar to that described by others in humans with Hashimoto's thyroiditis.

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Primary Extra-Nodal DLBCL of Glands: Our Experiences outside Guidelines of Treatment

Healthcare ◽

10.3390/healthcare9030286 ◽

2021 ◽

Vol 9 (3) ◽

pp. 286

Author(s):

Antonello Sica ◽

Mario Santagata ◽

Caterina Sagnelli ◽

Piero Rambaldi ◽

Renato Franco ◽

...

Keyword(s):

Lymph Node ◽

Cell Lymphoma ◽

B Cell Lymphoma ◽

Lymphoid Tissues ◽

Clinical Recovery ◽

Large B Cell Lymphoma ◽

Thyroid Glands ◽

Chemotherapy Protocol ◽

Large B Cell

Lymphomas usually involve lymph nodes and other lymphoid tissues, but sometimes occur in non-lymphoid organs, called extra-nodal sites. Primary diffuse extra-lymph node large B-cell lymphoma (DLBCL) of the thyroid and parotid gland have been observed rarely. According to the most accredited guidelines, primary extra-nodal DLBCL of the parotid and thyroid glands should be treated with three cycles of R-CHOP followed by radiotherapy of the involved site (ISRT). Surgery alone is not enough to treat DLBCL. We describe two unusual cases of primary extra-nodal DLBCL in elderly patients treated exclusively with surgical resection, given the inability to apply chemotherapy. Both patients achieved clinical recovery, which was maintained after a follow-up of more than 18 months, despite not having performed the indicated chemotherapy protocol. The two cases presented here, and a few others reported in the literature, should be considered exceptions to the rule, and do not allow the conclusion that surgery alone might be sufficient for complete remission.

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Infants Diagnosed with Athyreosis on Scintigraphy May Have a Gland Present on Ultrasound and Have Transient Congenital Hypothyroidism

Hormone Research in Paediatrics ◽

10.1159/000514989 ◽

2021 ◽

pp. 1-8

Author(s):

Niamh McGrath ◽

Colin Patrick Hawkes ◽

Stephanie Ryan ◽

Philip Mayne ◽

Nuala Murphy

Keyword(s):

Thyroid Gland ◽

Congenital Hypothyroidism ◽

Thyroid Tissue ◽

Thyroid Stimulating Hormone ◽

Thyroid Ultrasound ◽

Free T4 ◽

Median Serum ◽

Thyroid Glands ◽

Rule Out

Scintigraphy using technetium-99m (99mTc) is the gold standard for imaging the thyroid gland in infants with congenital hypothyroidism (CHT) and is the most reliable method of diagnosing an ectopic thyroid gland. One of the limitations of scintigraphy is the possibility that no uptake is detected despite the presence of thyroid tissue, leading to the spurious diagnosis of athyreosis. Thyroid ultrasound is a useful adjunct to detect thyroid tissue in the absence of 99mTc uptake. Aims: We aimed to describe the incidence of sonographically detectable in situ thyroid glands in infants scintigraphically diagnosed with athyreosis using 99mTc and to describe the clinical characteristics and natural history in these infants. Methods: The newborn screening records of all infants diagnosed with CHT between 2007 and 2016 were reviewed. Those diagnosed with CHT and athyreosis confirmed on scintigraphy were invited to attend a thyroid ultrasound. Results: Of the 488 infants diagnosed with CHT during the study period, 18/73 (24.6%) infants with absent uptake on scintigraphy had thyroid tissue visualised on ultrasound (3 hypoplastic thyroid glands and 15 eutopic glands). The median serum thyroid-stimulating hormone (TSH) concentration at diagnosis was significantly lower than that in infants with confirmed athyreosis (no gland on ultrasound and no uptake on scintigraphy) (74 vs. 270 mU/L), and median free T4 concentration at diagnosis was higher (11.9 vs. 3.9 pmol/L). Six of 10 (60%) infants with no uptake on scintigraphy but a eutopic gland on ultrasound had transient CHT. Conclusion: Absent uptake on scintigraphy in infants with CHT does not rule out a eutopic gland, especially in infants with less elevated TSH concentrations. Clinically, adding thyroid ultrasound to the diagnostic evaluation of infants who have athyreosis on scintigraphy may avoid committing some infants with presumed athyreosis to lifelong levothyroxine treatment.

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Mechanism of the Immediate Capillary Stress Response

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1957.188.2.387 ◽

1957 ◽

Vol 188 (2) ◽

pp. 387-394 ◽

Cited By ~ 5

Author(s):

Jenö Kramár ◽

William V. Meyers ◽

Harry H. McCarthy ◽

Nicholas Dietz ◽

Margarete Simay-Kramár ◽

...

Keyword(s):

Individual Differences ◽

Stress Response ◽

Potential Role ◽

Primary Effect ◽

Biphasic Response ◽

Capillary Stress ◽

Thyroid Glands ◽

Capillary Resistance ◽

Clinical Conditions ◽

Capillary Response

Two possibilities may be considered for the mechanism of the immediate capillary stress response: the direct nervous origin, and the humoral. The latter was investigated in this study. Immediate capillary stress response was found in the absence of the adrenal, pituitary or thyroid glands, and after removal of both the adrenals and the pituitary. Among the 10 physiologic substances considered as playing a potential role in this phenomenon, three were found to possess capillary activity. Vasopressin as well as oxytocin increases capillary resistance. Histamine gives rise to a biphasic response, involving a decrease of capillary resistance (primary effect) followed by an increase (due to vasopressin elicited by histamine). By means of these substances it is possible to duplicate the immediate capillary stress response. During the immediate capillary response plasma has antidiuretic and chloruretic properties—a finding compatible with an increased vasopressin concentration and with the assumption that vasopressin is discharged rather regularly in the first phase of the stress response. The immediate capillary stress response seems to be the result of an interplay between vasopressin-oxytocin, and histamine. Species and individual differences in the sensitivity to these substances may account for the various patterns of the capillary response. The possible significance of the immediate capillary response and of the increased vasopressin activity in some clinical conditions is discussed.

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