Plasma Thyroid Hormone Levels and Iodothyronine Deiodinase Activity Following an Acute Glucocorticoid Challenge in Embryonic Compared with Posthatch Chickens

Darras, Veerle; Kotanen, Stephen; Geris, Kris; Berghman, Luc; Kühn, Eduard

doi:10.1006/gcen.1996.0163

Cited by 109 publications

(69 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In acute treatments, with or without ventilation, the corticosterone concentration displayed a statistically significant positive correlation and triiodothyronine a significant negative correlation with body and facial temperature (p < 0.05), whereas the regression with ambient temperature was not significant. The responses of these hormones were found to be consistent with previously described physiological reactions to acute heat stress (Darras et al, 1996;Iqbal et al, 1990).…”

Section: Correlation Between Body Temperature and Facial Surface Tempsupporting

confidence: 86%

Infrared Thermography - Applications in Poultry Biological Research

Yahav¹,

Giloh²

2012

Infrared Thermography

View full text Add to dashboard Cite

Section: Correlation Between Body Temperature and Facial Surface Tempsupporting

confidence: 86%

Infrared Thermography - Applications in Poultry Biological Research

Yahav¹,

Giloh²

2012

Infrared Thermography

View full text Add to dashboard Cite

“…Administration of glucocorticoids [dexamethasone (Dex) or corticosterone] or ACTH to embryonic chickens increased plasma T 3 , decreased rT 3 concentrations, and decreased, or did not alter, plasma T 4 concentrations (4, 9). These treatments also increased conversion of T 4 to T 3 in the liver (4,9,15) and decreased hepatic type III deiodinase (4). Interaction between corticosterone and thyroid hormones has also been demonstrated during amphibian metamorphosis.…”

mentioning

confidence: 87%

“…The peak in plasma thyroid hormones during the final stages of development is characterized by an increase in 3,3Ј,5,5Ј-tetraiodothyronine (T 4 ), mediated by the HPT axis, and a concurrent increase in 3,3Ј,5-triiodothyronine (T 3 ), which is largely the result of an increase in deiodination of T 4 to T 3 and a decrease in T 3 degradation. Deiodination is the removal of iodine from iodothyronine molecules.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Glucocorticoids, thyroid hormones, and iodothyronine deiodinases in embryonic saltwater crocodiles

Shepherdley

Daniels

Orgeig

et al. 2002

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

. Glucocorticoids, thyroid hormones, and iodothyronine deiodinases in embryonic saltwater crocodiles. Am J Physiol Regul Integr Comp Physiol 283: R1155-R1163, 2002. First published June 20, 2002 10.1152/ajpregu.00015.2002We investigated the relationship between glucocorticoids, thyroid hormones, and outer ring and inner ring deiodinases (ORD and IRD) during embryonic development in the saltwater crocodile (Crocodylus porosus). We treated the embryos with the synthetic glucocorticoid dexamethasone (Dex), 3,3Ј,5-triiodothyronine (T3), and a combination of these two hormones (Dex ϩ T3). The effects of these treatments were specific in different tissues and at different stages of development and also brought about changes in plasma concentrations of free thyroid hormones and corticosterone. Administration of Dex to crocodile eggs resulted in a decrease in 3,3Ј,5,5Ј-tetraiodothyronine (T4) ORD activities in liver and kidney microsomes, and a decrease in the high-K m rT3 ORD activity in kidney microsomes, on day 60 of incubation. Dex treatment increased the T 4 ORD activity in liver microsomes, but not kidney microsomes, on day 75 of incubation. Dex administration decreased T 3 IRD activity in liver microsomes. However, this decrease did not change plasma-free T 3 concentrations, which suggests that free thyroid hormone levels are likely to be tightly regulated during development.

show abstract

“…In addition, we measured plasma cortisol levels concurrently with thyroid hormone levels. This was done because, to our knowledge, until now, there are no reports on the influence of transient hypothyroxinemia in preterm infants on adrenal cortex function, whereas glucocorticoid hormones and thyroid hormones are known to be functionally interrelated with respect both to maturational effects and to influencing each other's regulatory pathways (18,19).…”

mentioning

confidence: 99%

A Randomized, Masked Study of Triiodothyronine Plus Thyroxine Administration in Preterm Infants Less Than 28 Weeks of Gestational Age: Hormonal and Clinical Effects

et al. 2004

View full text Add to dashboard Cite

A randomized, placebo-controlled, masked study was conducted of the responses of thyroid parameters, cortisol, and the cardiovascular system to a single dose of triiodothyronine (T 3 ) 24 h after birth, followed by a daily dose of thyroxine (T 4 ) during 6 wk to infants Ͻ28 wk gestational age. Thirty-one infants were assigned to three groups: 1) group A: T 3 24 h after birth plus daily T 4 during 6 wk; 2) group B: placebo T 3 and T 4 during 6 wk; and 3) group C: placebo T 3 and placebo T 4 . T 4 , free T 4 , T 3 , free T 3 , reverse T 3 , thyroid-stimulating hormone, and cortisol were measured in cord blood and on days 1, 3, 7, 14, 21, 42, and 56. Data on pulse rate, blood pressure, and cumulative dose of inotropic agents were collected. T 3 (0.5 g/kg) resulted in a plasma increase until day 3. Thereafter, plasma T 3 levels were comparable between the groups. T 4 , free T 4 , and reverse T 3 were increased in groups A and B during the period of T 4 administration. Thyroid-stimulating hormone suppression was of shorter duration in group A. T 3 and T 4 administration did not have any effect on cortisol levels. We did not find any effects of T 3 or of T 4 administration on the cardiovascular system. A single injection of T 3 (0.5 g/kg) given 22-26 h after birth only leads to a 2-d increase of T 3 levels and does not have effects on the cardiovascular system. This study does not support the use of T 3 according to our regimen in preterm infants. Thyroid hormones play an important role in normal growth and development of the CNS (1, 2). In term infants, thyroxine (T 4 ) and triiodothyronine (T 3 ) increases shortly after birth. In premature infants, transient hypothyroxinemia after birth is a common finding (3-7). This hypothyroxinemia is characterized by low levels of T 4 and T 3 , which do not cause elevations in thyroid-stimulating hormone (TSH) above 20 mU/L. The degree of hypothyroxinemia is related to gestational age (GA) and the severity of neonatal disease. Low T 3 and T 4 levels in premature infants have been found to be associated with poor neurologic and developmental outcome (8 -11).Transient hypothyroxinemia is a multicausal phenomenon in which immaturity of thyroid hormone metabolism with high activity of deiodinase type 3 together with factors such as immaturity of the hypothalamo-pituitary-thyroid axis and the sudden interruption of the maternal contribution to fetal thyroid hormone pools are involved. Thyroid hormone supplementation in preterm infants has been the subject of several clinical studies with clinical and neurodevelopmental parameters as primary outcome (12)(13)(14). To date, no clear effect of supplemental T 4 treatment on neurodevelopmental outcome has been demonstrated. In an earlier study, however, we observed that a subgroup of T 4 -treated infants of Ͻ29 wk GA tended to have a better developmental outcome than infants of similar GA in the placebo group (13,15).T 4 administration to preterm infants of Ͻ30 wk GA did not result in increased plasma T 3 levels; in fact, it resulted in de...

show abstract

Plasma Thyroid Hormone Levels and Iodothyronine Deiodinase Activity Following an Acute Glucocorticoid Challenge in Embryonic Compared with Posthatch Chickens

Cited by 109 publications

References 0 publications

Infrared Thermography - Applications in Poultry Biological Research

Infrared Thermography - Applications in Poultry Biological Research

Glucocorticoids, thyroid hormones, and iodothyronine deiodinases in embryonic saltwater crocodiles

A Randomized, Masked Study of Triiodothyronine Plus Thyroxine Administration in Preterm Infants Less Than 28 Weeks of Gestational Age: Hormonal and Clinical Effects

Contact Info

Product

Resources

About