Related Experiment Videos
Effect of 131I treatment on the calcitonin response to calcium infusion in hyperthyroid patients
M Tzanela1, N C Thalassinos, A Nikou
1Department of Endocrinology, Evangelismos Hospital, Athens, Greece.
Objective:
The objective was to evaluate the effect of 131I treatment for hyperthyroidism on calcitonin secretion by thyroid C-cells.
Design:
Determination of basal calcitonin levels and calcitonin secretory reserve before and after 131I administration.
Patients:
Seventeen hyperthyroid patients (15 female, two male) were studied before, and 2 months after 131I treatment, and 12 of these patients were restudied 8 months after 131I treatment.
Measurements:
Calcitonin response was assessed by measuring basal and post calcium infusion calcitonin levels. Basal TSH, T3, and T4 levels were also determined at each study.
Results:
The rise of plasma calcium resulted in statistically significant increase of plasma calcitonin levels before 131I treatment (10.9 +/- 2.4 pmol/l), while this response was significantly diminished 2 and 8 months after treatment (2.6 +/- 0.7 and 1.6 +/- 0.3 pmol/l, respectively). No correlation was found between the calcitonin response and age or plasma TSH.
Conclusion:
Our results demonstrate that 131I treatment for hyperthyroidism may seriously damage thyroid C-cells and cause calcitonin deficiency.