Open AccessDifferences in the Binding of Thyroid Hormones and Indoles by Rat α 1 ‐Fetoprotein and Serum Albumin
Author(s) -
HERVÉ Françoise,
GRIGOROVA AnneMarie,
RAJKOWSKI Krzysztof,
CITTANOVA Nicole
Publication year - 1982
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1982.tb06482.x
Subject(s) - albumin , hormone , fetus , medicine , endocrinology , tryptophan , serum albumin , chemistry , thyroid , alpha (finance) , fetal protein , thyroid hormones , blood proteins , biology , biochemistry , amino acid , pregnancy , construct validity , nursing , patient satisfaction , genetics
The transport of small molecules in the blood, normally assured by serum albumin in the adult. is not well known in the fetus since the albumin concentration is low in fetal serum and inversely related to the α 1 ‐fetoprotein concentration. In order to investigate whether rat α 1 ‐fetoprotein might be a fetal counterpart to albumin. the binding properties of these two proteins have been compared with respect to a series of molecules of biological importance, especially during fetal development: thyroid hormones and indole analogues. Though high‐affinity binding of thyroxine was found with both rat α 1 ‐fetoprotein and albumin, a significant difference in the number of binding sites for this hormone was found with the two protcins. Further, while rat serum albumin strongly bound L‐tryptophan and indolyl‐3‐acetic acid (K a ∼ 10 5 M −1 ), rat α 1 ‐fetoprotein did not bind any of the indoles tested. These results are discussed with respect to the physiological and pharmacological significance of the transport role of these proteins.