Growth hormone therapy in normal short children induces a transitory decrease in plasma growth hormone releasing hormone levels and in human growth hormone responsiveness to exogenous growth hormone releasing hormone
Gil-Ad, I.; Klinger, B.; Pertzelan, A.; Erster, B.; Silbergeld, A.; Talpaz, H.; Laron, Z.
Journal of Endocrinological Investigation 15(10): 735-739
ISSN/ISBN: 0391-4097 PMID: 1362733 DOI: 10.1007/bf03347642
A three-month study of the effect of growth hormone (hGH) therapy (0.1 U/kg/day sc) on plasma levels of GH releasing hormone (GHRH), somatostatin and insulin-like growth factor I (IGF-I) and on the hGH responsiveness to exogenous GHRH was carried out in 32 prepubertal short-stature children with normal GH secretion. Blood samples were collected prior to initiation of therapy, and at 5, 30 and 90 days of onset of therapy, as well as 2 and 90 days after termination of therapy. The nonconventional hGH therapy induced an increase in serum IGF-I levels which lasted as long as therapy was continued. Plasma GHRH levels showed an early transitory decrease after five days of therapy, whereas plasma somatostatin levels were unaltered. A slight suppression in hGH responsiveness to exogenous GHRH was found at 2 but not at 90 days after termination of hGH therapy. It is concluded that nonconventional hGH treatment does not cause permanent changes in physiological hGH secretion.