Daily injection of 8IU of methionyl human growth hormone (met-hGH), produced by recombinant DNA technology, was performed in healthy young volunteers. Daily injections for four days did not cause any significant change in the results of physical examination, electrocardiogram, blood count or urinalysis.
Non-esterified fatty acid levels increased significantly at 4hours after the first injection of met-hGH in a manner similar to pituitary human growth hormone (pithGH). Both hGHs caused a significant increase in serum somatomedin A during the four daily injections. Plasma hGH reached peak levels at 3-4hours after im injection of met-hGH and 4-6hours after pit-hGH. The levels were 19.5±1.6 and 21.3±2.8ng/ml, respectively. After iv one bolus administration of 4IU hGH to two volunteers, plasma hGH reached peak levels at 5minutes at mean levels of 292ng/ml after methGH and 293ng/ml after pit-hGH. The half life of the two hGHs was 17.2 and 17.1 minutes, respectively, according to the disappearance curve measured after iv administration.