Effect of different human growth hormone preparations on nitrogen retention in hypopituitary children

Butenandt, O., Bidlingmaier, F. and Knorr, D. (Department of Paediatrics, University of Munich, Germany). Effect of different human growth hormone preparations on nitrogen retention in hypopituitary children. Acta Paediatr Scand, 63: 549, 1974.—The biologic activity of three different preparations of human growth hormone (HGH) obtained with the methods of Raben, Reisfeld and Roos respectively were compared in nitrogen retention tests in 18 patients with hypopituitarism and in 17 children with familial shortness of stature. HGH Raben produced a mean nitrogen retention of 30.9% in 11 hypopituitary patients and no retention in the control group, HGH Reisfeld was followed by a retention of 19.7% in the 9 hypopituitary patients and an elevated excretion of 12% in the control group, and HGH Roos evoked a retention of 33.2% only in the 9 hypopituitary children. HGH Reisfeld had a lesser response in consecutive tests with different HGH preparations in the same patients than the other two HGH preparations. The dilution curve of HGH Reisfeld obtained with a double antibody radio immunoassay did not parallel a dilution curve of a reference hormone from the National Institute of Health whereas the other two preparations had identical dilution curves. It is concluded that the method of extraction alters the biologic activity of the hormone as well as the physico-chemical properties.