Growth hormone regulation by growth hormone-releasing hormone in infant rhesus monkeys.
To study the relationship of endogenous GHRH to the changes seen in serum GH concentration in neonatal primates, we administered antiserum to GHRH (GHRH-Ab) or GHRH antagonist, (N-Acetyl-Tyr1,D-Arg2)GHRH-(1-29)-NH2, to unanesthetized, fasted rhesus monkeys, 1-31 days of age, via an acutely placed venous catheter. The administration of GHRH-Ab resulted in a significant decrease in serum GH concentration at 1-2 and 7-9 days, but not at 28-31 days of age. The administration of GHRH antagonist resulted in a significant decrease in serum GH concentrations at 1-2 days, but not at 7 or 14 days of age. These results imply that basal serum GH is more dependent on endogenous GHRH at 1-2 days than after 7-28 days of age. This suggests developmental changes in the hypothalamic regulation of GH secretion with advancing age in the neonatal period.
Wheeler
M D
MD
Department of Pediatrics, University of California-Davis, School of Medicine.
Wehrenberg
W W
WW
Styne
D M
DM
D000818:Animals; D000831:Animals, Newborn; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D013007:Growth Hormone-Releasing Hormone / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D008253:Macaca mulatta; D010446:Peptide Fragments / Q000494:pharmacology; D017337:Sermorelin / Q000031:analogs & derivatives*
D010446:Peptide Fragments; D017337:Sermorelin; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone; C058677:somatotropin releasing hormone (1-29)amide, N-acetyl-tyrosyl(1)-arginyl(2)-