14102 studies
Two complete and two partial structure-activity relationship scans of the active fragment of human growth hormone-releasing hormone, [Nle27]-hGHRH(1-29)-NH2, have identified potent agonists in vitro. Single-point replacement of each amino acid by ala…
Based on our previous results, in conjunction with various structural considerations, 19 new analogs of the GHRH antagonist [PhAc-Tyr1,D-Arg2,Phe(pCl)6,Abu15,Nle27,Agm29]++ +hGHRH(1-29) (MZ-5-156) were synthesized by the solid-phase method. These com…
GH-releasing peptide-6 (GHRP-6) is a potent GH secretagogue that releases GH by uncertain mechanisms. To assess whether GHRH is required for GH release by GHRP-6 in humans, we used the specific antagonist to GHRH (N-Ac-Tyr1,D-Arg2)GHRH(1-29)NH2 (GHRH…
OBJECTIVE: This study evaluated the effect of corticotrophin-releasing hormone (CRH) on growth hormone releasing hormone (GHRH)-stimulated growth hormone (GH) release in man. DESIGN: Six healthy adult volunteers (age 20-35 years) were studied. On dif…
It has been shown that G proteins are potential regulatory molecules in the transmembrane signaling cascade. The aim of this study was to examine the possibility of equivalent G-protein redistribution and/or down-regulation in a target cell upon agon…
Insulin-like growth factors I and II (IGF-I and -II) are potent mitogens for various cancers, including carcinoma of the prostate. In several experimental cancers, treatment with antagonists of growth hormone-releasing hormone (GH-RH) produces a redu…
The novel synthetic growth hormone-releasing heptapeptide GHRP-1 is reported to be more potent than growth hormone-releasing hormone (GHRH) in eliciting GH release in vivo in rats and man. However, in ovine pituitary cells in primary culture in a per…
Effect of growth hormone-releasing peptide-2 (GHRP-2) on ovine somatotrophs is abolished by a growth hormone-releasing factor (GRF) receptor antagonist, which raises the possibility that GHRP-2 may act on GRF receptors. In the present study, we used…
Hexarelin (Hex) is a synthetic hexapeptide with potent GH-releasing activity in both animals and men. Aim of this study was to evaluate the GH response to a maximal dose of Hex and GH-releasing hormone (GHRH) in a group of patients with Prader-Willi…
The GHRP-6 seems to act at a pituitary site, activating different intracellular messenger pathways from those utilized by GHRH, and at the hypothalamic level where receptors for GHRP-6 have been demonstrated. This study examines the effect of GHRP-6…
Our objective was to examine the influence of feeding and endogenous GH secretion on circulating IGF-I in colostrum-deprived newborn pigs fed colostrum (n = 4), formula (control, n = 4), or water (n = 4). In another four formula-fed pigs, GH was abla…
Several earlier studies have shown that some human pituitary GH-secreting somatotrophinomas are able to synthesise and release hypothalamic GHRH and it has been proposed that a positive autocrine feedback loop involving this tumor-derived GHRH may pa…
SECMA 1 is a polypeptide purified from a green algeae of the Ulva species by several gel chromatographies, showing the following sequence (Glu-Asp-Arg-Leu-Lys-Pro). In order to determine the effect of SECMA 1 on human skin fibroblasts extracellular m…
BACKGROUND: A novel gastric pentadecapeptide, BPC 157, has been shown to attenuate different lesions (i.e., gastrointestinal tract, liver, pancreas, somatosensory neurons). This suggests an interaction with the dopamine system. When used alone, BPC 1…
1. The pharmacokinetics of three new peptidyl growth hormone secretagogues, ipamorelin (NNC 26-0161), NNC 26-0194 and NNC 26-0235, were compared with two well-known hexapeptides, GHRP-2 and GHRP-6, in the male rat following different routes of admini…
The development and pharmacology of a new potent growth hormone (GH) secretagogue, ipamorelin, is described. Ipamorelin is a pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2), which displays high GH releasing potency and efficacy in vitro and in vivo. As…
A novel class of growth hormone-releasing compounds with a molecular weight in the range from 500 to 650 has been discovered. The aim of this study was to obtain growth hormone secretagogues with oral bioavailability. By a rational approach we were a…
A new series of GH secretagogues derived from ipamorelin is described. In an attempt to obtain oral bioavailability, by reducing the size and the number of potential hydrogen-bonding sites of the compounds, a strategy using the peptidomimetic fragmen…
Antimicrobial peptides of several structural classes have been found in phagocytes and epithelial cells of many animals. The broadly microbicidal protegrins (PG1, -2, and -3) were originally isolated as 16 to 18-amino-acid peptides from pig neutrophi…