title: Normal circulating immunoreactive growth hormone releasing factor (hGRF) concentrations in patients with functional hypothalamic hGRF deficiency.
abstract: Using a highly specific radioimmunoassay we have measured the concentrations of human growth hormone releasing factor (ir-hGRF) in the peripheral circulation of six individuals with acquired hypothalamic hGRF deficiency. Despite their hypothalamic dysfunction venous plasma ir-hGRF increased normally in every patient after the stimulus of a mixed breakfast, from an average concentration basally of 13.6 +/- 6.0 pg/ml to a maximum of 29.0 +/- 8.4 pg/ml (mean +/- SEM) at 120 min. The findings indicate that circulating hGRF is at least in large part extrahypothalamic in origin, which in turn implies a physiological role for hGRF in the periphery.
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D013006:Growth Hormone / Q000378:metabolism; D013007:Growth Hormone-Releasing Hormone / Q000097:blood / Q000172:deficiency*; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism; D007328:Insulin; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments; D017337:Sermorelin
chemical_list: D007328:Insulin; D010446:Peptide Fragments; D017337:Sermorelin; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone