The Peripheral Metabolism of Triiodothyronine in Normal Subjects and in Patients with Hyperthyroidism
Overview
Authors
Affiliations
In order to assess the contribution of 3.3',5-triiodo-L-thyronine (T(3)) to overall thyroid hormone economy, conjoint measurements of the kinetics of peripheral T(3) metabolism and the total concentration of T(3) in serum were made in a group of normal subjects and in a group of patients with hyperthyroid Graves' disease. As judged from the disappearance of trichloroacetic acid-precipitable (131)I from serum after a single intravenous dose of labeled T(3), the following mean values were obtained in the normal subjects: volume of distribution, 43 liters or 0.62 liter/kg; fractional turnover rate. 52% per 24 hr: clearance rate, 22.3 liters/24 hr: and absolute disposal rate, 60 mug/24 hr. In the patients with untreated hyperthyroidism, values for all these functions were greatly increased. After treatment, the volume of T(3) distribution returned to normal but the fractional turnover rate remained abnormally rapid.
Pharmacokinetics of L-Triiodothyronine in Patients Undergoing Thyroid Hormone Therapy Withdrawal.
Van Tassell B, Wohlford 4th G, Linderman J, Smith S, Yavuz S, Pucino F Thyroid. 2019; 29(10):1371-1379.
PMID: 31364488 PMC: 6797066. DOI: 10.1089/thy.2019.0101.
Hypothyroidism in the elderly: pathophysiology, diagnosis and treatment.
Laurberg P, Andersen S, Bulow Pedersen I, Carle A Drugs Aging. 2005; 22(1):23-38.
PMID: 15663347 DOI: 10.2165/00002512-200522010-00002.
Influence of thyroid dysfunction on drug pharmacokinetics.
Shenfield G Clin Pharmacokinet. 1981; 6(4):275-97.
PMID: 6166422 DOI: 10.2165/00003088-198106040-00003.
The extrathyroidal conversion rate of thyroxine to triiodothyronine in normal man.
Pittman C, Chambers Jr J, READ V J Clin Invest. 1971; 50(6):1187-96.
PMID: 5578229 PMC: 292048. DOI: 10.1172/JCI106596.
Triiodothyronine radioimmunoassay.
Lieblich J, UTIGER R J Clin Invest. 1972; 51(1):157-66.
PMID: 5007046 PMC: 332941. DOI: 10.1172/JCI106786.