Time course of thyroid hormone concentration in the blood of completely or partially thyroidectomized rats

Abstract

Complete or partial thyroidectomy, adapted to adult animals, resulted in a permissible mortality (less than 5%) during and after the intervention. Blood concentrations of thyroid hormones were compared in intact, sham-operated animals, and animals with 100, 75, 50, and 25%-removed thyroid in various periods after the operation. The results indicate high stability of thyroid function to mechanical injury and its high regeneration potential. A conclusion on the gland damage after exposure of the organism to pathogenetic factors can be made only after repeated measurements of blood concentrations of thyroid hormones if a typical time course of their changes is observed. The authors suggest that complete removal of visible part of the gland with subsequent thyrostatic therapy leading to athyroxinemia be called total thyroidectomy, complete removal of visible part of the gland associated with pronounced long hypothyroxinemia be called subtotal thyroidectomy, and removal of any fragment of the gland be called partial thyroidectomy.