Premium
THYROGLOBULIN OF VARYING MOLECULAR SIZES WITH DIFFERENT DISAPPEARANCE RATES IN PLASMA FOLLOWING SUBTOTAL THYROIDECTOMY
Author(s) -
FELDTRASMUSSEN ULLA,
PETERSEN P. H.,
NIELSEN H.,
DATE J.,
MADSEN C. M.
Publication year - 1978
Publication title -
clinical endocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 147
eISSN - 1365-2265
pISSN - 0300-0664
DOI - 10.1111/j.1365-2265.1978.tb02201.x
Subject(s) - thyroglobulin , medicine , endocrinology , thyroidectomy , plasma levels , thyroid
SUMMARY To investigate the possible presence of thyroglobulin (Tg) of different molecular sizes in plasma, blood specimens were drawn from patients during and after surgery for thyroid adenoma. Tg was measured in all serum samples by a radioimmunoassay. Selected samples were fractionated on a sepharose CL‐6B column, and the fractions were assayed for Tg antigen. In serum drawn at maximum Tg concentration, molecular weights of Tg antigen ranging from 660,000 (19S) to less than 100,000 were found. 6 h later the Tg antigen of mol. wt. < 100,000 could not be detected, and after 3 days only 19S Tg was present. Correspondingly the plasma Tg concentration vs. time curve showed a biphasic course from which two half‐lives could be estimated. For 19S Tg, t a 1/2 , had a mean value of 4.3 days, whereas the over‐all half‐life for the mixture of smaller molecules, t b 1/2 . had a mean value of 3.7 h. The smaller molecules also showed different antigenic reactivity in the assay indicating an altered structure of the molecules. The assumption that this might be due to lack of sialic acid would explain the faster catabolic rate. Preliminary results from this study have been presented at the 11th FEBS Meeting in Copenhagen, 1977, and at the European Thyroid Association 8th Meeting in Lyon, 1977.