Abstract
Human thyrotrophic hormone (hTSH) was infused into three euthyroid male volunteers; thereafter, it declined in the serum with a mean half-life of 77 min. The mean metabolic clearance rate (MCR) was 40 ml/min while the mean production rate (PR) was 99 mu/day. The mean distribution space (DS) was 4.5 litres from which the exchangeable TSH in this space was calculated as 8.4 mU. Serum TSH also declined with a similar half-life of 80 minutes at the conclusion of an infusion of thyrotrophic hormone releasing hormone (TRH) into two normal human volunteers.
Serum triiodothyronine (T3) and thyroxine (T4) levels were monitored during and after the TSH infusions. Although the secretion of both was stimulated, the rise of T3 was more rapid and pronounced than that of T4.
Key words
Human Thyrotrophic Hormone - Kinetics - Triiodothyronine and Thyroxine Response
