Wikipedia

Reverse triiodothyronine

Also found in: Medical.
Reverse triiodothyronine
Skeletal formula of reverse triiodothyronine
Ball-and-stick model of the reverse triiodothyronine molecule as a zwitterion
Names
IUPAC name
(2S)-2-Amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3-iodophenyl]propanoic acid
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
IUPHAR/BPS
KEGG
MeSH Reverse+triiodothyronine
UNII
CompTox Dashboard (EPA)
Properties
Chemical formula
C15H12I3NO4
Molar mass 650.974
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Reverse triiodothyronine (3,3’,5’-triiodothyronine, reverse T3, or rT3) is an isomer of triiodothyronine (3,5,3’ triiodothyronine, T3).

Reverse T3 is the third-most common iodothyronine the thyroid gland releases into the bloodstream, at 0.9%; tetraiodothyronine (levothyroxine, T4) constitutes 90% and T3 is 9%. However, 95% of rT3 in human blood is made elsewhere in the body, as enzymes remove a particular iodine atom from T4.[1]

The production of hormone by the thyroid gland is controlled by the hypothalamus and pituitary gland. The physiological activity of thyroid hormone is regulated by a system of enzymes that activate, inactivate or simply discard the prohormone T4 and in turn functionally modify T3 and rT3. These enzymes operate under complex direction of systems including neurotransmitters, hormones, markers of metabolism and immunological signals.

The levels of rT3 increase in conditions such as euthyroid sick syndrome because its clearance decreases while its production stays the same. The decreased clearance is possibly from lower Thyroxine 5-deiodinase activity in the peripheral tissue or decreased liver uptake of rT3.[2] In addition, increased rT3 concentrations result from upregulated Thyroxine 5-deiodinase activity in critical illness, starvation and fetal life.[3]

Reactions

Synthesis of Reverse T3 from T4 via deiodination. Synthesis of T3 and T2 is also shown.

References

  1. ^ Chopra IJ (July 1976). "An assessment of daily production and significance of thyroidal secretion of 3, 3', 5'-triiodothyronine (reverse T3) in man". J. Clin. Invest. 58 (1): 32–40. doi:10.1172/JCI108456. PMC 333152. PMID 932209.
  2. ^ Euthyroid Sick Syndrome at eMedicine
  3. ^ Chatzitomaris, Apostolos; Hoermann, Rudolf; Midgley, John E.; Hering, Steffen; Urban, Aline; Dietrich, Barbara; Abood, Assjana; Klein, Harald H.; Dietrich, Johannes W. (20 July 2017). "Thyroid Allostasis–Adaptive Responses of Thyrotropic Feedback Control to Conditions of Strain, Stress, and Developmental Programming". Frontiers in Endocrinology. 8. doi:10.3389/fendo.2017.00163. PMC 5517413. PMID 28775711.

External links

This article is copied from an article on Wikipedia® - the free encyclopedia created and edited by its online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of Wikipedia® encyclopedia articles provide accurate and timely information, please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.

Copyright © 2003-2025 Farlex, Inc Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.