Abstract
We investigated the serum concentration of IGF-II in patients with thyroid diseases (25 with untreated Graves' patients, 30 with hypothyroidism, 23 with thyroid adenoma) and in 72 healthy adults as normal controls, by a sensitive radioimmunoassay of serum IGF-II. Thyroid hormones are known to increase IGF-I production in the liver through the enhancement of GH secretion. In case of IGF-II, however, knowledge has been rather limited. The mean ±SD concentration in healthy subjects was 556 ±94μg/L with neither sex nor age dependence. In untreated Graves' patients, serum IGF-II levels (675 ±129μg/L) were significantly (P<0.01) higher than in normal controls, and significantly lower in patients with hypothyroidism (460±106μg/L; P<0.01). Thyroid hormones revealed positive correlation with the IGF-II concentration.
