GH response to an iv bolus of growth-hormone-releasing hormone (GHRH 1ò44, 2 μg/kg iv) was evaluated in 17 prepubertal children with total GH deficiency (GHD), 6 with partial GHD and in 7 prepubertal normal but short children tested as control. GH response to conventional pharmacological (insulin and arginine or L-Dopa) and physiological stimuli (sleep test) and to GHRH test was also compared. GHRH-induced GH peak occurred at variable times and marked heterogeneity in magnitude of the individual responses to this peptide was observed in GHD patients and in controls. GH increases after GHRH with a peak > 10 ng/ml suggested an hypothalamic origin of the GHD in 12 patients (8 with total GHD and 4 with partial GHD). A significant difference (p <0.025) of GH peak mean following GHRH administration between total GHD children and normal short children was found. GH response to GHRH injection was usually higher than to conventional stimuli. Nevertheless GH peak following GHRH administration was lower than GH peak following conventipnal stimuli in 6 children (2 partial GHD children and 4 normal ones). A normal short child failed to respond to GHRH test performed twice. GHRH test is an important diagnostic tool in order to point out hypothalamic GHD.
- GHRH test
- growth hormone
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism