[Skip to Content]
[Skip to Content Landing]
Article
October 1970

Serum Thyroxine Resin Uptake of Liothyronine I 125, and Free Thyroxine Index

Author Affiliations

Orange, Calif

From the Department of Medicine, Orange County Medical Center, Orange, Calif, and the University of California, Irvine. Dr. Sarin is now in New Delhi.

Arch Intern Med. 1970;126(4):631-634. doi:10.1001/archinte.1970.00310100077008
Abstract

Thyroxine (T4) in serum was determined by competitive protein-binding analysis, the resin uptake of liothyronine I 125 (RT3) was measured, and a "free T4 index" was calculated as the mathematical product of values for T4 iodine (T4I) and RT3. Pregnant euthyroid patients and normal women taking estrogens had high values for T4I associated with low values for RT3. Sick euthyroid patients tended to have decreased values for T4I with high values for RT3. The free T4 index accurately reflected the state of thyroid function in euthyroid patients with disturbances of T4-binding proteins, as well as in patients with hyperthyroidism or hypothyroidism.

References
1.
Murphy BEP, Pattee CJ:  Determination of thyroxine utilizing the property of protein-binding.  J Clin Endocr 24:187-196,1964.Crossref
2.
Murphy BP:  The determination of thyroxine by competitive protein-binding analysis employing an anion-exchange resin and radio thyroxine.  J Lab Clin Med 66:161-167,1965.
3.
Murphy BEP, Pattee CJ, Gold A:  Clinical evaluation of a new method for the determination of serum thyroxine.  J Clin Endocr 26:247-256,1966.Crossref
4.
Robbins J, Rall JE:  The iodine-containing hormones , in Gray CH, Bacharach AL, (eds):  Hormones in Blood , ed 2. New York, Academic Press Inc, 1967, vol 1, pp 383-490.
5.
Oppenheimer JH:  Role of plasma proteins in the binding, distribution and metabolism of the thyroid hormones.  New Eng J Med 278:1153-1162, 1968.Crossref
6.
Clark F, Horn DB:  Assessment of thyroid function by the combined use of the serum protein-bound iodine and resin uptake of 131I-triiodothyronine.  J Clin Endocr 25:39-45,1965.Crossref
7.
Anderson BG:  Free thyroxine in serum in relation to thyroid function.  JAMA 203:577-582,1968.Crossref
8.
Kennedy JA, Abelson DM:  Determination of serum thyroxine using a resin sponge technique.  J Clin Path 20:89-94, 1967.Crossref
9.
Cassidy CE, Benotti J, Peno S:  Clinical evaluation of the determination of thyroxine iodine.  J Clin Endocr 28:420-421,1968.Crossref
10.
Arango G, Mayberry WE, Hockert TJ, et al:  Total and free human serum thyroxine in normal and abnormal thyroid states.  Mayo Clin Proc 43:503-516,1968.
11.
Sparagna M, Phillips G, Kucera L:  Serum thyroxine by competitive protein-binding analysis: Clinical, statistical, and comparative evaluation.  J Clin Endocr 29:191-199, 1969.Crossref
12.
Kaihara S, Carulli N, Wagner HN Jr:  Comparison of radioisotopic and column chromatographic assay of serum thyroxine.  J Nucl Med 10:281-283, 1969.
13.
Howorth PJN, Maclagan NF:  Clinical application of serum-total-thyroxine estimation, resin uptake, and freethyroxine index.  Lancet 1:224-228,1969.Crossref
14.
Clark F, Horn DB:  Relationship between serum protein-bound iodine and resin uptake of 131I-triiodothyronine.  J Clin Endocr 26:352-353, 1966.Crossref
×