A synthetic analog of growth hormone-releasing hormone (GHRH 1-29) previously FDA-approved for diagnosing and treating growth hormone deficiency in children.
The effects of intranasal insufflation of the synthetic growth hormone releasing factor GRF 1-29-NH2 on serum growth hormone (GH) were investigated in five healthy prepubertal children with short stature. 100 micrograms/kg/body weight of synthetic GR…
Human growth hormone releasing hormone (GHRH) was originally extracted from two pancreatic tumours in patients with acromegaly, and is now known to consist of a 44 residue amidated peptide or its C-terminal-shortened derivatives. The sequence of rat…
A synthetic 29-amino acid analogue of human pancreatic GH-releasing hormone (GHRH(1-29)NH2) has recently been shown to stimulate the release of GH in normal subjects. We have studied the GH response to GHRH(1-29)NH2 in nine children irradiated for br…
In order to investigate whether the impaired GH secretion associated with hypothyroidism and hyperthyroidism is due to a hypothalamic or a pituitary disorder, we have studied plasma GH responses to GH-releasing factor (1-29) (GRF) in euthyroid, hypot…
It is unclear whether growth hormone releasing factor (GRF) administration in vivo may desensitize the somatotroph. To investigate this possibility we have examined the effects of 10-h infusion of the equipotent 1-29 amide analogue of hpGRF on serum…
To determine whether the 29 amino-acid fragment of growth hormone releasing hormone (GHRH) can be combined with other hypothalamic releasing hormones in a single test of anterior pituitary reserve, the responses of anterior pituitary hormones to comb…
It is well known that muscarinic cholinergic blockade either reduces or abolishes stimulated GH release in normal subjects. In this study we have investigated whether cholinergic muscarinic blockade could reduce the GH responses to GRF 1-29 and TRH i…
Growth hormone (GH) responses to GRF (1 microgram/kg BW i.v.) were investigated. Comparison between GRF(1-40) and GRF(1-29)NH2 in 11 young adult volunteers gave identical results. One hundred and thirty-one children and adolescents (45 with idiopathi…
Continuous infusion of GHRH, as well as a bolus injection of GHRH, specifically stimulates the release of GH by the anterior pituitary. However, repetitive bolus injections of GHRH result in diminished responses of GH, while a constant infusion of GH…
Growth hormone releasing factor (GRF) is one of two main releasing hormones which control pituitary hGH production and release. This activity is retained even when the length of the GRF polypeptide is reduced to the 29 N-terminal residues. This 29-re…
The ability of 30 synthetic GRF(1-29)-NH2 analogs to stimulate adenylate cyclase activity was investigated in membranes from rat adenopituitary, rat liver and rat pancreas. In adenopituitary membranes, GRF and GRF analogs interacted with specific GRF…
(125I-His1, D-Ala2, Nleu27)-growth hormone-releasing factor (GRF) (1-29)-NH2, initially developed as a possible radioligand for identifying GRF receptors in the anterior pituitary, was found to bind to rat hepatic membranes. The tracer was stable, bo…
Previous research on the favorable effects of mild conformational restriction in the N-terminal region of glucagon has led us to carry out analogue studies on the sequence-related 1-12 region of GRF(1-29)NH2. Replacement of each of the first 11 amino…
It is well known that hypothyroidism is frequently associated with impaired GH responses to different stimuli. In the present study we have evaluated GH responses to GH-releasing factor (GRF) in patients with primary hypothyroidism before and during…
A 29 amino acid analog of growth hormone releasing hormone (GH-RH)-40 was given intravenously, subcutaneously, and intranasally to normal men to determine its effectiveness in stimulating growth hormone (GH) release. The GH-RH analog, [Nle27]GH-RH(1-…
The functions of the Trp-25 and Met-27 residues and the free carboxy terminus of glucagon have been debated for many years. Despite some semi-synthetic data to the contrary, comparison of the glucagon sequence with the other 5 members of this family…
The first twenty-nine amino acids of human Growth Hormone Releasing Factor (hGRF) possess a distinct amphiphilic character. This is seen as twisted hydrophobic and hydrophilic bands in the helical net projection. Four amidated analogs were designed b…
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 dy…
In order to establish the influence of dopaminergic, alpha-adrenergic and cholinergic pathways on GRF-mediated GH release we have studied the GH responses to GRF 1-29 (100 or 50 micrograms as i.v. bolus) alone and in combination with metoclopramide (…
Adenylate cyclase activity was studied in anterior pituitary homogenates from young adult (6 months) and old (20 and 24 months) male rats. Basal, NaF-, GTP-, 5'-guanylimidodiphosphate (Gpp(NH)p)- and forskolin-stimulated activities were similar in th…