A METHOD FOR DEMONSTRATING GROWTH HORMONE ACTIVITY IN HUMAN PLASMA*

Abstract

A method was described for concentration of growth hormone added to human plasma. The plasma was fractionated according to the method of Cohn et al. The added growth hormone was recovered in fraction B (Conn''s fractions IV-1 and IV-4). About 25% of the hormone was recovered in 15% of the total plasma protein. In fractionated plasma of young pigs and a calf, growth hormone-like activity was demonstrated in a concentration of 40-50 ug/100 ml of plasma. No growth hormone activity was found in fractionated, or lyophilized plasma from normal human blood. Growth hormone-like activity was demonstrated in fractionated, or lyophilized plasma of retroplacental blood in plasma from the umbilical cord blood and in plasma from 2 patients with acromegaly and gigantism. At present it is impossible to say whether this growth-promoting activity is identical with that of the pituitary growth hormone.