Radioimmunoassay of Human Growth Hormone Using Ion Exchange Resin

Abstract

A simple technique for the radioimmunoassay of human growth hormone (HGH) using HGH-I131, rabbit anti-HGH serum and an anion exchange resin to separate the bound and free HGH-I131 is described. The method, which is sensitive (lower limit 0.4 m [mu]g/ml) and reliable, has been used to measure HGH in the unextracted serum of normals, acromegalics and patients with hypopituitarism. Fasting serum HGH levels in 46 normal subjects, aged from 3 to 81 years, ranged from 0.6 to 7.7 [mu]g/ml, with a mean of 2.6 mug/ml. In 16 acromegalics the fasting HGH levels ranged from 3.4 to 900 [mu]g/ml. Combined with tolubtamide-induced hypoglycemia, the method was used to investigate pituitary function before and after cryogenic hypophysectomy.