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E Oliveira, E G Moura, A P Santos-Silva, A T S Fagundes, A S Rios, Y Abreu-Villaça, J F Nogueira Neto, M C F Passos and P C Lisboa

birth cohort study: role of breast-feeding . International Journal of Obesity and Related Metabolic Disorders 27 162 – 172 . Bianco AC Kim BW 2006 Deiodinases: implications of the local control of thyroid hormone action . Journal of

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L Johnsen, A H Kongsted and M O Nielsen

adulthood. Others ( Dutra et al . 2003 , Lisboa et al . 2008 ) have reported that neonatal protein and energy restriction in suckling rats led to adult hyperthyroidism and increased liver deiodinase activity. However, long-term effects of fetal exposures

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J Kwakkel, W M Wiersinga and A Boelen

. NTI, among others, is characterized by low serum T 3 levels and decreased liver deiodinase type 1 (D1) activity ( Peeters et al. 2003 , Wiersinga 2005 ). It has been shown that proinflammatory cytokines are capable of decreasing liver D1 mRNA

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Shu-Fang Xia, Xiao-Mei Duan, Xiang-Rong Cheng, Li-Mei Chen, Yan-Jun Kang, Peng Wang, Xue Tang, Yong-Hui Shi and Guo-Wei Le

to the serum profiles of TH in obesity, it is widely accepted that iodothyronine deiodinases in central and peripheral tissues determine tissue-specific TH levels and TH primarily exerts their actions through interaction with TRs, and finally

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Luana Lopes Souza, Aline Cordeiro, Lorraine Soares Oliveira, Gabriela Silva Monteiro de Paula, Larissa Costa Faustino, Tania Maria Ortiga-Carvalho, Karen Jesus Oliveira and Carmen Cabanelas Pazos-Moura

TRβ ( Thrb – forward: 5′-TGGGCGAGCTCTATATTCCA-3′, reverse: 5′-ACAGGTGATGCAGCGATAGT-3′); mGPD ( Gpd2 – forward: 5′-ATTTCCCCATGCTCCAGAAG-3′, reverse: 5′-ACCTCCATGTAATTGGCCG-3′); and type 1 deiodinase (D1; Dio1 – forward: 5′-CTT GGA GGT GGC TAC GG-3

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Cecilia Verga Falzacappa, Eleonora Timperi, Barbara Bucci, Donatella Amendola, Piero Piergrossi, Davide D'Amico, Maria Giulia Santaguida, Marco Centanni and Silvia Misiti

Materials and Methods section. Results represent the mean± s.e.m . of three separate experiments. Thyroid hormone receptors, transporters, and deiodinases are expressed in rGROV cells To assess that our cell model was appropriate for thyroid hormone action

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Riccardo Dore, Luka Levata, Sogol Gachkar, Olaf Jöhren, Jens Mittag, Hendrik Lehnert and Carla Schulz

iBAT and iWAT In the iBAT, i.c.v. administration of nesfatin-1 (100 pmol/rat) significantly increased the mRNA expression of iodothyronine deiodinase 2 ( Dio2 ) ( t (9) = −2.99, P  < 0.05; +370%) and tended to increase that of Ucp1 ( t (9) = −1

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P. Laurberg and N. Boye

ABSTRACT

In previous studies we have found that the cholecystographic contrast agent ipodate induced a rapid, sustained and reversible inhibition of thyroxine (T4) secretion from perfused dog thyroid lobes. This type of inhibition of thyroid secretion has not been observed previously. To evaluate whether this effect is unique for ipodate, ten other iodine-containing radiographic contrast agents were tested. The four agents used for cholecystography (iocetamate, iodipamide, ioglycamate and iotroxate) all induced rapid inhibition of T4 secretion from TSH-stimulated perfused dog thyroid lobes, while none of six agents predominantly excreted through the kidneys (amidotrizoate, metrizamid, metrizoate, iodamide, diodone and ioxithalamate) influenced T4 secretion significantly. All the cholecystographic agents inhibited T4 deiodinases from dog thyroid and liver. Diodone also inhibited the deiodinases while none of the other compounds tested had any effect.

The results indicate that the structure necessary to inhibit thyroid secretion is common to a number of cholecystographic agents and that it could be related to the structure responsible for the inhibitory effect of cholecystographic agents on T4 deiodinases.

J. Endocr. (1987) 112, 387–390

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VM da Costa, DG Moreira and D Rosenthal

The effects of aging on human or animal thyroid function are still not well defined. We evaluated some aspects of thyroid function during aging using an animal model (young and old Dutch-Miranda rats). In old rats of both genders, serum thyroxine (T4) decreased but serum thyrotrophin (TSH) remained unaltered, suggesting a disturbance in the pituitary-thyroid feedback mechanism during aging. Serum tri-iodothyronine (T3) only decreased in old males, possibly because female rats are almost twice as efficient in hepatic T4 to T3 deiodination. Thyroidal T4-5'-deiodinase activity did not change much during aging, although it decreased slightly in males. Thyroidal iodothyronine-deiodinase type I mRNA expression but not total thyroidal enzymatic activity were higher in female than in male rats. Thus, ovarian/testicular hormones may modulate the expression and/or the activity of hepatic and thyroidal type I iodothyronine-deiodinase. Thyroperoxidase (TPO) and thyroglobulin (Tg) expression were higher in young male rats than in females. In males, TPO and Tg gene expression decreased with aging, suggesting that androgens might increase their expression. Our results showed that aging induces real changes in rat thyroid gland function and regulation, affecting at least pituitary, thyroid and liver functions. Furthermore, some of these changes were gender related, indicating that gonadal hormones may modulate thyroid gland function and regulation.

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P. A. Janssens, J. A. Grigg, H. Dove and A. J. Hulbert

ABSTRACT

The levels of thyroid hormones in the plasma and the activities of 5′-deiodinase activity in liver and kidney were determined in the tammar wallaby, Macropus eugenii, from early pouch life to adulthood. The total concentration of plasma thyroxine (T4) was below 15 nmol/l before day 75 of pouch life, rose to about 75 nmol/l at day 160, and then decreased to about 12 nmol/l in the adult. The total concentration of plasma tri-iodothyronine (T3) was below 0·4 nmol/l before day 120, increased to 3 nmol/l by about day 220 and then decreased to 1·0 nmol/l in adults. Concentrations of free T4 and free T3 followed a similar pattern but peaked at 45 and 160 pmol/l respectively. Concentrations of reverse T3 (rT3) were extremely variable, ranging from 0 to 1 nmol/l at day 100, and from 0 to > 2 nmol/l at day 180. After about day 230, rT3 levels fell rapidly and were below 0·3 nmol/l in adults. Liver and kidney 5′-deiodinase activities, which were undetectable before day 80, reached adult levels by day 220. Half-maximal activity of both these enzymes occurred at about day 205, mid-way between the peaks of T4 and T3. These findings suggest that the systems supporting synthesis and release of hormones from the thyroid gland are probably mature by about day 160 of pouch life in the tammar, while peripheral deiodinase activity, which is a major factor in the production of T3 in the plasma, matures by about day 220. These events thus precede the development of physiological independence of the young tammar from its mother.

Journal of Endocrinology (1990) 127, 427–436