rT3 might be beneficial for brain function

Iritu1021

Breaking Through The Fog
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https://www.invivoclinical.co.uk/invivo-education/articles/clearing-up-the-confusion-about-reverse-t3--part-2--the-role-of-reverse-t3-in-thyroid-assessment

There is no credible scientific evidence that rT3 enters the nucleus of the cell at all, and the bulk of the scientific literature states clearly that rT3 does not bind to, and has no known transcriptional activity at, the thyroid receptor. It is, however, known to have potent activity in the cytoplasm as an initiator of actin polymerization in astrocytes in the brain [7]. This is mediated in a non-genomic manner by its binding to a very specific thyroid receptor that exists only in the extranuclear compartment. Actin polymerization is important to cell structure and motility, and particularly important to normal brain development.
 

Iritu1021

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@Iritu1021 , this is all very interesting, but I keep wondering why they won't name that "very specific thyroid receptor".
I don't know why they phrased it like that. The original study doesn't mention any specific receptor, only the experimental observation that T4 and rT3 had the effect on the cellular cytoskeleton but T3 didn't have any effect.
http://www.jbc.org/content/265/9/5296.short

Astrocytes grown without thyroxine also showed a disorganized actin cytoskeleton, and 10 nM thyroxine or 10 nM reverse triiodothyronine normalized the actin cytoskeleton appearance within 20 min; 10 nM 3,3',5-triiodothyronine had no effect.
 

Iritu1021

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@Iritu1021 , thanks and I'll have to read this several times because tomorrow I was going to try and schedule an rT3 test.
Personally, I find it to be a rather useless test. I have not found any significant correlation between my well being and my rT3 levels.
 

Paralee

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I've been wanting some kind of base level other than one I got a few years ago. I think I'll put it off and read some more. Thanks for the info.