Endocrinologia Japonica
Online ISSN : 2185-6370
Print ISSN : 0013-7219
ISSN-L : 0013-7219
Radioimmunoassay of Urinary Calcitonin in Normal Subjects and in Patients with Medullary Carcinoma of the Thyroid
SHIGETO MORIMOTOTOSHIO ONISHIYOSHIAKI OKADASHOUSHI LEESHUNJI IMANAKAKEISUKE FUKUOHIROSHI KONOYUICHI KUMAHARA
Author information
JOURNAL FREE ACCESS

1982 Volume 29 Issue 1 Pages 1-10

Details
Abstract
A simple technique for measuring urine calcitonin (CT) was established using a sensitive radioimmunoassay (RIA) system for plasma human calcitonin (hCT). To extract urinary CT, urine samples were fractioned by gel chromatography on a column (0.8×20cm) of Bio Gel P-2. Recovery of synthetic (1-32) hCT was 86.1±6.2% and the intra-and inter-assay coefficients of variation in RIA were 5.9 and 8.2%, respectively. Dilution curves of the urinary CT after gel-filtration were parallel with the standard curve. In 11 patients with medullary carcinoma of the thyroid (MCT), the CT levels of the urine (in ng/mg Cr) were 3.4 to 20.8 times higher than those of the plasma (in ng/ml), and a significant positive correlation (r=0.93, P<0.001) was obtained between the urinary and plasma levels of CT in these 11 patients. In 32 normal subjects, the CT levels of the urine (in pg/mg Cr) were only 0.41 to 5.1 times of those of the plasma (in pg/ml), and a weak positive correlation (r=0.408, P<0.05) was obtained between these two levels. However, urinary CT levels in normal subjects apparently reflected a rise in endogenous plasma hCT in response to calcium infusion (4mg/kg B.W. for 1min) and that of exogenous plasma CT when synthetic (1-32) hCT (500μg for 1min)
Following gel filtration on a Bio Gel P-30 1.5×80cm column, larger molecular forms of CT than (1-32) hCT were found in the urine not only patients with MCT but also of normal subjects after infusion of calcium or synthetic (1-32) hCT. was injected intravenously.
It is concluded that measurement of urine CT is useful not only for diagnosis of MCT but also for evaluating CT metabolism in normal subjects.
Content from these authors
© The Japan Endocrine Society
Next article
feedback
Top