CoChat
Sign Up
Cited by 223Thyroid Disorders and TreatmentsThyroid Cancer Diagnosis and TreatmentAdrenal Hormones and Disorders

Determination of iodothyronine absorption and conversion of L-thyroxine (T4) to L-triiodothyronine (T3) using turnover rate techniques

Open access
Surks, Martin I., Schadlow, Alan R., Stock, Jerrold M., Oppenheimer, Jack H.·1973·Journal of Clinical Investigation
DOI 10.1172/jci107244PMC PMC302327
Open this paper in CoChat — free accountOpen PDF

Abstract

The absorption of L-thyroxine (T(4)) and L-triiodothyronine (T(3)) and the fractional rate of conversion of T(4) to T(3) were determined from the turnover rates of T(4) and T(3) in seven patients without endogenous thyroid function during separate treatment periods with these iodothyronines. Serum T(3) concentration was measured by a radioimmunoassay procedure in which the iodothyronines are separated from the plasma proteins before incubation with anti-T(3) antibody. Metabolic clearance rates were calculated by an integral (noncompartmental) approach since the use of single compartment kinetics led to a 40% overestimation of the metabolic clearance rate of T(3). Based on the amount of hormone ingested and the observed hormonal turnover rates, the absorption of T(4) and T(3) (iodothyronine turnover/iodothyronine ingested) in man could be estimated. Absorption of T(3) was complete in three subjects but decreased to 43% in a fourth who was suffering from mild congestive heart failure. Mean T(4) absorption was 48.0+/-2.6% (SEM) for seven subjects. The mean fractional rate of T(4) to T(3) conversion determined during T(4) replacement therapy (T(3) turnover/T(4) turnover) was 42.6% (range 30.7-50.8%). Thus, approximately one-half of the T(4) which was deiodinated was converted to T(3) suggesting that monodeiodination is an obligatory step in the peripheral metabolism of T(4). Calculations based on these results together with other available data suggest that under normal physiologic circumstances the major portion of the T(3) pool is derived from monodeiodination of T(4).

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1172/jci107244

Cites

36 of 36 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • A rare case of TH malabsorption was reported to be induced by congestive heart failure, which may cause intestinal dysfunction and chronic passive congestion of the liver.

    “In addition, a rare case of TH malabsorption was reported to be induced by congestive heart failure, which may cause intestinal dysfunction and chronic passive congestion of the liver (63).”

    From Levothyroxine: conventional and novel drug delivery formulations. (2023) · cites this paper as [63]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

1 of the 37 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Related

Authors
Surks, M. I., Schadlow, A. R., Stock, J. M., & Oppenheimer, J. H.
Affiliations
Albert Einstein College of Medicine (US)
Venue
Journal of Clinical Investigation
Publisher
American Society for Clinical Investigation
Published
1973-04-01
Volume
52
Issue
4
Pages
805-811
ISSN
0021-9738 (ISSN-L)
DOI
10.1172/jci107244
PMC
PMC302327
OpenAlex
W2160583708
Cited by
223
References
37
Citations by year
2023: 1 · 2022: 1 · 2021: 1 · 2019: 6 · 2018: 2 · 2017: 1 · 2016: 2 · 2014: 2 · 2013: 2 · 2012: 2
FWCI
16.87
Type
journal article
Language
en
Open access
Locations
  • Journal of Clinical Investigation (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Disorders and Treatments
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Cancer Diagnosis and Treatment
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Adrenal Hormones and Disorders
Keywords
triiodothyronine, T4 to T3 conversion, metabolic clearance rate, thyroid hormone replacement, congestive heart failure, non-compartmental analysis
MeSH terms
Absorption, Humans, Hypothyroidism, Iodine Isotopes, Kinetics, Metabolic Clearance Rate, Methods, Radioimmunoassay, Thyroxine, Triiodothyronine

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review