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.
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.
Institute of Pediatric and Adolescent Endocrinology, Beilinson Medical Center, Petah Tiqva, Israel.
I
I
Gil-Ad
B
B
Klinger
A
A
Pertzelan
B
B
Erster
A
A
Silbergeld
H
H
Talpaz
Z
Z
Laron
D000293:Adolescent; D002648:Child; D005260:Female; D013006:Growth Hormone / Q000009:adverse effects* / Q000097:blood / Q000627:therapeutic use; D013007:Growth Hormone-Releasing Hormone / Q000097:blood*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007457:Iodine Radioisotopes; D008297:Male; D013004:Somatostatin / Q000097:blood
D007457:Iodine Radioisotopes; D013004:Somatostatin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone