Thyroid function in goitrous subjects with thyroxine binding globulin deficiency

1983 ◽  
Vol 102 (4) ◽  
pp. 527-530 ◽  
Author(s):  
F. P. Callan ◽  
M.J. Duffy ◽  
G.J. Duffy ◽  
R.J. Farrell ◽  
T.J. McKenna
Keyword(s):  
Thyroid Hormone ◽  
Protein Binding ◽  
Thyroid Activity ◽  
Free Triiodothyronine ◽  
Thyroxine Binding Globulin ◽  
The Family ◽  
Euthyroid Status ◽  
Thyroid Hormone Levels ◽  
Euthyroid Goitre ◽  
Tsh Levels

Abstract. The co-existence of thyroxine binding globulin (TBG) deficiency and euthyroid goitre in the same family raised the possibility that the disorders might be related. However, although both disorders co-existed in some members of the family, other members had either but not both conditions. These observations exclude the possibility that goitre development was solely due to alterations in thyroid activity brought about by TBG deficiency. It is possible, however, that the defect in protein binding might have enhanced goitre development in predisposed individuals as the two largest goitres occurred in TBG deficient subjects. Of the conventional parameters used to assess thyroid hormone levels in TBG deficient subjects, only the free triiodothyronine index consistently reflected the euthyroid status of these patients as established by clinical examination and TSH levels.

scholarly journals Thyroid testing paradigm switch from thyrotropin to thyroid hormones—Future directions and opportunities in clinical medicine and research

Endocrine ◽  
2021 ◽  
Vol 74 (2) ◽  
pp. 285-289
Author(s):  
Stephen P. Fitzgerald ◽  
Nigel G. Bean ◽  
James V. Hennessey ◽  
Henrik Falhammar
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Dysfunction ◽  
Clinical Medicine ◽  
Older Individuals ◽  
Free Triiodothyronine ◽  
Thyroid State ◽  
Peripheral Tissues ◽  
Hormone Levels ◽  
Thyroid Hormone Levels ◽  
Tsh Levels

Abstract Purpose Recently published papers have demonstrated that particularly in untreated individuals, clinical parameters more often associate with thyroid hormone, particularly free thyroxine (FT4), levels than with thyrotropin (TSH) levels. Clinical and research assessments of the thyroid state of peripheral tissues would therefore be more precise if they were based on FT4 levels rather than on TSH levels. In this paper we describe implications of, and opportunities provided by, this discovery. Conclusions The FT4 level may be the best single test of thyroid function. The addition of free triiodothyronine (FT3) and TSH levels would further enhance test sensitivity and distinguish primary from secondary thyroid dysfunction respectively. There are opportunities to reconsider testing algorithms. Additional potential thyroidology research subjects include the peripheral differences between circulating FT4 and FT3 action, and outcomes in patients on thyroid replacement therapy in terms of thyroid hormone levels. Previously performed negative studies of therapy for subclinical thyroid dysfunction could be repeated using thyroid hormone levels rather than TSH levels for subject selection and the monitoring of treatment. Studies of outcomes in older individuals with treatment of high normal FT4 levels, and pregnant women with borderline high or low FT4 levels would appear to be the most likely to show positive results. There are fresh indications to critically re-analyse the physiological rationale for the current preference for TSH levels in the assessment of the thyroid state of the peripheral tissues. There may be opportunities to apply these research principles to analogous parameters in other endocrine systems.

scholarly journals Analysis of Hypothalamic TRH Neurons in Regulating Thyroid Hormone Levels

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A849-A849
Author(s):  
Ricardo H Costa e Sousa ◽  
Rodrigo Rorato ◽  
Anthony Neil Hollenberg ◽  
Kristen R Vella
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormone Receptor ◽  
Designer Drugs ◽  
Mrna Levels ◽  
Hormone Levels ◽  
Males And Females ◽  
Thyroid Hormone Levels ◽  
Hpt Axis ◽  
Tsh Levels

Abstract Thyroid hormone (TH) is a major regulator of development and metabolism. An important mechanism controlling TH production is the negative feedback at the hypothalamic and pituitary level and it has been suggested that thyroid hormone receptor β (TRβ) is the main mediator of TH actions in the hypothalamic paraventricular nucleus (PVN). Nevertheless, the direct actions of TH and TRβ in the negative regulation of TRH have yet to be demonstrated in vivo. Here we used two approaches to investigate the TRH neuron. First, we used a chemogenetic tool to directly investigate the role of TRH neurons on the regulation of thyroid hormone levels. Mice expressing Cre-recombinase in TRH neurons received bilateral injections of the activating designer receptors exclusively activated by designer drugs (DREADD) directly into the PVN. Activation of TRH neurons produced a rapid and sustained increase in circulating TSH levels in both males and females. TSH levels increased approximately 10-fold from baseline within 15 minutes of injection of CNO, returning to baseline within 2.5 hours. TH levels were increased approximately 2-fold in males and females. Therefore, using a chemogenetic approach, we were able to directly evaluated the role of PVN TRH neurons on the control of thyroid activity, for the first time. Next, we generated mice deficient in TRβ specifically in neurons expressing melanocortin 4 receptor (MC4R), which overlaps with TRH expression in the PVN. Knockout mice (KO) developed normally and showed no change in TH and TSH levels. TRH mRNA levels in the PVN of KO mice were similar to control mice. To investigate if the deletion of TRβ in the PVN changes the sensitivity of the HPT axis to T3, mice were rendered hypothyroid and given increasing doses of T3 for 2 weeks. Results show no difference in TRH mRNA or serum TSH between controls and KO. Surprisingly, despite the presence of detectable genomic recombination on the TRβ gene in the PVN, there was no difference in TRβ mRNA expression between control and KO mice, suggesting that either MC4R-positive neurons do not express TRβ or they represent a very small population of TRβ-positive cells in the PVN. Present data show that TRH neuron activation rapidly stimulates TSH release and increases TH levels, demonstrating a major role of these neurons in the regulation of the hypothalamic-pituitary-thyroid (HPT) axis. Nevertheless, deletion of TRβ from MC4R neurons had no major effect on either TRH or TH levels in in mice. Additionally, TRβ in MC4R-positive TRH neurons in the PVN is not necessary for TH-induced suppression of TRH mRNA. Although further studies are necessary, these data suggest that there are distinct populations of hypophysiotropic TRH neurons in the PVN, some of which are not regulated by thyroid hormone and TRβ.

Developmentally regulated thyroid hormone distributor proteins in marsupials, a reptile, and fish

2005 ◽  
Vol 288 (5) ◽  
pp. R1264-R1272 ◽  
Author(s):  
Samantha J. Richardson ◽  
Julie A. Monk ◽  
Caroline A. Shepherdley ◽  
Lars O. E. Ebbesson ◽  
Frank Sin ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Sea Bream ◽  
Aqueous Environment ◽  
Critical Periods ◽  
Developmentally Regulated ◽  
Thyroxine Binding Globulin ◽  
Hormone Levels ◽  
Thyroid Hormone Levels ◽  
Lipid Environment

Thyroid hormones are essential for vertebrate development. There is a characteristic rise in thyroid hormone levels in blood during critical periods of thyroid hormone-regulated development. Thyroid hormones are lipophilic compounds, which readily partition from an aqueous environment into a lipid environment. Thyroid hormone distributor proteins are required to ensure adequate distribution of thyroid hormones, throughout the aqueous environment of the blood, and to counteract the avid partitioning of thyroid hormones into the lipid environment of cell membranes. In human blood, these proteins are albumin, transthyretin and thyroxine-binding globulin. We analyzed the developmental profile of thyroid hormone distributor proteins in serum from a representative of each order of marsupials ( M. eugenii; S.crassicaudata), a reptile ( C. porosus), in two species of salmonoid fishes ( S. salar; O. tshawytsch), and throughout a calendar year for sea bream ( S. aurata). We demonstrated that during development, these animals have a thyroid hormone distributor protein present in their blood which is not present in the adult blood. At least in mammals, this additional protein has higher affinity for thyroid hormones than the thyroid hormone distributor proteins in the blood of the adult. In fish, reptile and polyprotodont marsupial, this protein was transthyretin. In a diprotodont marsupial, it was thyroxine-binding globulin. We propose an hypothesis that an augmented thyroid hormone distributor protein network contributes to the rise in total thyroid hormone levels in the blood during development.

scholarly journals Familial Dysalbuminemic Hyperthyroxinemia in a Japanese Man Caused by a Point Albumin Gene Mutation (R218P)

2016 ◽  
Vol 7 ◽  
pp. JCM.S38990 ◽  
Author(s):  
Yoshinori Osaki ◽  
Yoshitaka Hayashi ◽  
Yoshinori Nakagawa ◽  
Katsumi Yoshida ◽  
Hiroshi Ozaki ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Autosomal Dominant ◽  
Japanese Patients ◽  
Free Triiodothyronine ◽  
Serum Free ◽  
Albumin Gene ◽  
Dominant Disease ◽  
Euthyroid Hyperthyroxinemia ◽  
Aomori Prefecture ◽  
Tsh Levels

Familial dysalbuminemic hyperthyroxinemia (FDH) is a familial autosomal dominant disease caused by mutation in the albumin gene that produces a condition of euthyroid hyperthyroxinemia. In patients with FDH, serum-free thyroxine (FT4) and free triiodothyronine (FT3) concentrations as measured by several commercial methods are often falsely increased with normal thyrotropin (TSH). Therefore, several diagnostic steps are needed to differentiate TSH-secreting tumor or generalized resistance to thyroid hormone from FDH. We herein report a case of a Japanese man born in Aomori prefecture, with FDH caused by a mutant albumin gene (R218P). We found that a large number of FDH patients reported in Japan to date might have been born in Aomori prefecture and have shown the R218P mutation. In conclusion, FDH needs to be considered among the differential diagnoses in Japanese patients born in Aomori prefecture and showing normal TSH levels and elevated FT4 levels.

Effects of triiodothyronine supplementation following modified Fontan procedure

1997 ◽  
Vol 7 (2) ◽  
pp. 194-200 ◽  
Author(s):  
Richard D. Mainwaring ◽  
John J. Lamberti ◽  
Jerald C. Nelson ◽  
Glenn F. Billman ◽  
Thomas L. Carter ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Clinical Outcome ◽  
Fontan Procedure ◽  
Length Of Hospital Stay ◽  
Free Triiodothyronine ◽  
Low Cardiac Output ◽  
Total Triiodothyronine ◽  
Total Thyroxine ◽  
Thyroid Hormone Levels ◽  
Previous Series

AbstractPatients undergoing the modified Fontan procedure may develop low cardiac output postoperatively. Since thyroid hormone has important effects on cardiovascular function, the present study was undertaken to evaluate the influence of triiodothyronine supplementation. Ten consecutive patients under-going the Fontan procedure were administered intravenous triiodothyronine (0.4 mcg per kg) following surgery. Clinical outcome and thyroid hormone profiles were assessed and then compared to a previous series of patients undergoing the Fontan procedure who had not received triiodothyronine supplementation. Both groups initially demonstrated marked decreases in serum free triiodothyronine levels. The group which received triiodothyronine supplementation demonstrated a more rapid return of serum triiodothyronine levels to baseline [259±17 vs 121±15 pg/dl (p<0.05) on the fifth postoperative day and 336±18 vs 178±12 pg/dl (p<0.05) on the eighth day]. In addition, patients receiving supplemental triiodothyronine demonstrated more rapid recovery of total triiodothyronine, free thyroxine, total thyroxine and thyroglobulin levels. The group which received triiodothyronine supplementation had a shorter length of hospital stay [9±2 vs 14±3 (p<0.05)] as compared to patients who did not receive exogenous triiodothyronine. The results of this study demonstrate that triiodothyronine supplementation aids in the recovery of thyroid hormone levels following Fontan procedure. This endocrinologic finding correlated with improved clinical outcome.

Deficient pulsatile thyrotropin secretion in the low-thyroid-hormone state of severe non-thyroidal illness

1994 ◽  
Vol 130 (2) ◽  
pp. 132-136 ◽  
Author(s):  
Nicola Custro ◽  
Vincenza Scafidi ◽  
Salvatore Gallo ◽  
Alberto Notarbartolo
Keyword(s):  
Thyroid Hormone ◽  
Healthy Subjects ◽  
Normal Subjects ◽  
Healthy Individuals ◽  
Circadian Variations ◽  
Tsh Secretion ◽  
Thyroid Hormone Levels ◽  
Rhythmic Change ◽  
Serum Tsh ◽  
Tsh Levels

Custro N, Scafidi V, Gallo S, Notarbartolo A. Deficient pulsatile thyrotropin secretion in the low-thyroid-hormone state of severe non-thyroidal illness. Eur J Endocrinol 1994;130:132–6. ISSN 0804–4643. Twenty-four-hour thyrotropin (TSH) profiles in eight severely ill patients were compared with those of six healthy subjects. The profiles were assessed using the cosinor method to evaluate circadian variations and using the Pulsar algorithm to analyze episodic secretion. In the normal subjects, the typical periodicity of TSH secretion showed a mean level in the rhythm (mesor) of 2.03 mU/l, The amplitude (half the extent of rhythmic change in the cycle) was 0.58 mU/l; the acrophase (the delay from midnight (0 degrees) of the highest level in the rhythm) was −9.9 degrees. In contrast, severely ill patients showed only slight and anticipated elevations of serum TSH levels (mesor 0.93 mU/l, amplitude 0.22 mU/l, acrophase +82.4 degrees). Moreover, whereas the episodic TSH secretion in healthy individuals consisted of 5–8 pulses/24 h, mainly clustered around midnight, only one pulse of reduced amplitude was detected in two of the eight severely ill patients and no pulses in the other six. Since earlier studies have indicated that the loss of TSH pulsatility is associated with the relative insensitivity of the thyrotrophs to low thyroid hormone levels and our analytical procedures have demonstrated that 24 h pulsatile pattern of TSH closely overlapped with baseline TSH secretion, it seems reasonable to assume that low-thyroid-hormone state, deficient pulsatile TSH secretion and altered nyctohemeral TSH periodicity do not coincide by chance, but that there is a causal relationship between such abnormalities in severely ill patients. Nicola Custro, Cattedra di Patologia Medica, Via del Vespro, n.141, 90127 Palermo, Italy

Bombesin inhibits thyrotrophin secretion in rats

1985 ◽  
Vol 108 (1) ◽  
pp. 79-84 ◽  
Author(s):  
Terunori Mitsuma ◽  
Tsuyoshi Nogimori ◽  
Masahiro Chaya
Keyword(s):  
Thyroid Hormone ◽  
Plasma Concentrations ◽  
Treated Group ◽  
Inhibitory Effect ◽  
Thyrotrophin Releasing Hormone ◽  
Tsh Secretion ◽  
The Central Nervous System ◽  
Thyroid Hormone Levels ◽  
Tsh Levels

Abstract. The effects of peripheral administration of bombesin on thyrotrophin-releasing hormone (TRH) and thvrotrophin (TSH) secretion in rats were studied. Bombesin (200 μg/kg) was injected iv, and the rats were serially decapitated. TRH, TSH and thyroid hormone were measured by radioimmunoassay. The hypothalamic immunoreactive TRH (ir-TRH) content increased significantly after bombesin injection, whereas plasma concentrations tended to decrease, but not significantly. Plasma TSH levels decreased significantly in a dose-related manner with a nadir at 40 min after the injection. Plasma thyroid hormone levels did not change significantly. Plasma ir-TRH and TSH responses to cold were inhibited by bombesin, but the plasma TSH response to TRH was not affected. In the pimozide- or para-chlorophenylalanine pre-treated group, the inhibitory effect of bombesin on TSH levels was prevented, but not in the l-Dopa- or 5-hydroxytryptophan pre-treated group. These drugs alone had no effect on plasma TSH levels in terms of the dose used. The inactivation of TRH immunoreactivity in plasma or hypothalamus in vitro after bombesin injection did not differ from that of the controls. These findings suggest that bombesin acts on the hypothalamus to inhibit TRH release, and that its effects are at least partially modified by amines of the central nervous system.

scholarly journals The immune status of preschool children with diffuse enlargement of the thyroid under ecologically adverse conditions

1995 ◽  
Vol 41 (3) ◽  
pp. 23-25
Author(s):  
L. N. Ulanova ◽  
А. М. Zemskov ◽  
V. I. Knyazev
Keyword(s):  
Preschool Children ◽  
Thyroid Hormone ◽  
Functional Activity ◽  
Immune Status ◽  
Close Correlation ◽  
Hormone Deficiency ◽  
Equal Frequency ◽  
Thyroid Activity ◽  
Adverse Conditions ◽  
Tsh Levels

A total of 434 children aged 4 to 7 living under ecologically adverse conditions were examined. Diffuse enlargement of the thyroid was detected in 35% of children (I degree in 62%, II degree in 38%), with equal frequency in boys and girls. This research was aimed at assessing the immune status of children with enlargement of the thyroid of different degree and at estimation of the functional activity of the thyroid by clinical and laboratory signs (T3, T4, TSH, whose concentrations were measured by standard radioimmunoassay and enzyme immunoassay). Preschool children with diffuse enlargement of the thyroid presented with immunocyte depression in the blood, which was evidently a result of thyroid hormone deficiency at the level of cellular metabolism, because the function of tire enlarged thyroid was frequently reduced, that is, compensated or decompensated hypothyroid state was present. Immunologic disturbances depended on the degree of diffuse enlargement of the gland and on the presence and degree of thyroid activity reduction. A close correlation between blood T4 and TSH levels and immunity status parameters was detected.

Thyroid hormone levels in Tortoises (Testudo spp.) depending on Season and Sex

2021 ◽  
Author(s):  
Christoph Leineweber ◽  
Sabine Öfner ◽  
Karina Mathes ◽  
Hans-Peter Piepho ◽  
Rachel E. Marschang ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Rank Correlation ◽  
Information Criterion ◽  
Reference Intervals ◽  
Free Triiodothyronine ◽  
Seasonal Differences ◽  
Hormone Levels ◽  
Testudo Graeca ◽  
Thyroid Hormone Levels

Thyroid hormones and the factors influencing them are rarely studied in tortoises. This study therefore aimed to calculate reference intervals (RI) for specific species, sexes, and seasons for thyroid hormones and iodine levels in blood of four adult Mediterranean tortoise species and to evaluate possible correlations between thyroid hormones, serum iodine, plasma protein and increased liver and kidney values. Thyroid hormones (total tetraiodothyronine [tT4], free tetraiodothyronine [fT4], total triiodothyronine [tT3], and free triiodothyronine [fT3]) were measured in plasma from adult, healthy Hermann´s (Testudo hermanni, n = 255), spur-thighed (Testudo graeca, n = 89), marginated (Testudo marginata, n = 72), and Russian tortoises (Testudo horsfieldii, n = 30). Species, sex and season specific variations were determined by Bayesian information criterion (BIC) and correlations between plasma thyroid hormones, protein, iodine and increased liver/kidney values were evaluated by Spearman’s rank correlation test. Total T4 did not reveal any species, sex, or seasonal differences (RI 0.102 to 0.455 µg/dL), while seasonal differences were found for fT4 (RI spring 0.624 to 9.012; summer 0.379 to 5.476; fall 0.376 to 5.426 pmol/L). The tT3 levels differed significantly depending on species, season, and the interaction of species x season. Seasonal differences were also found for fT3 and iodine. Several significant (p &lt; 0.05) correlations were detected between the tested analytes, especially positive correlations between tT4 and fT4. These results provide a tool for the evaluation of thyroid hormone levels in Mediterranean tortoises and indicate the influence of season on the thyroid in these animals.

scholarly journals Association of High Vitamin D Status with Low Circulating Thyroid-Stimulating Hormone Independent of Thyroid Hormone Levels in Middle-Aged and Elderly Males

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Qingqing Zhang ◽  
Zhixiao Wang ◽  
Min Sun ◽  
Mengdie Cao ◽  
Zhenxin Zhu ◽  
...  
Keyword(s):  
Vitamin D ◽  
Thyroid Hormone ◽  
Smoking Status ◽  
Thyroid Stimulating Hormone ◽  
Vitamin D Status ◽  
Middle Aged ◽  
Hormone Levels ◽  
Elderly Males ◽  
Thyroid Hormone Levels ◽  
Tsh Levels

Background. A recent study has reported that high circulating 25-hydroxyvitamin D [25(OH)D] is associated with low circulating thyroid-stimulating hormone (TSH) levels, but only in younger individuals. The goal of the present study was to explore the relationship between vitamin D status and circulating TSH levels with thyroid autoimmunity and thyroid hormone levels taken into consideration in a population-based health survey of middle-aged and elderly individuals.Methods. A total of 1,424 Chinese adults, aged 41–78 years, were enrolled in this cross-sectional study. Serum levels of 25(OH)D, TSH, thyroid hormones, and thyroid autoantibodies were measured.Results. The prevalence of vitamin D insufficiency was 94.29% in males and 97.22% in females, and the prevalence of vitamin D deficiency was 55.61% in males and 69.64% in females. Vitamin D status was not associated with positive thyroid autoantibodies after controlling for age, gender, body mass index, and smoking status. Higher 25(OH)D levels were associated with lower TSH levels after controlling for age, FT4 and FT3 levels, thyroid volume, the presence of thyroid nodule(s), and smoking status in males.Conclusion. High vitamin D status in middle-aged and elderly males was associated with low circulating TSH levels independent of thyroid hormone levels.

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