Peptide Hormones: GHRP-2
GHRP-2, like GHRP-6, is a synthetic growth hormone releasing peptide that is only 6 amino acids in length. Unlike GHRP-6, GHRP-2 is thought to act directly through the growth hormone secretagogue receptor.
GHRP-2 is available orally, intranasally and of course through subcutaneous or intravenous injection. Given intranasally, the dose is 5-20 ug/kg while subcutaneously, the dose would be about 2 ug/kg.
One of the draw backs to the use of GHRP-6 is its short half-life or about 20 minutes. Like GHRP-6, GHRP-2 has a short half-life but is quite potent. In the literature, daily administration of GHRP-2 has been shown to reduce its effect on GH release.
Along with increases in GH, GHRP-2 has been shown to increase IGF-1 levels. It is also worth noting that increases were also seen in IGF binding proteins 3 and 5. Like ghrelin, GHRP-2 has been shown to cause a significant increase in appetite.
