GHRP-6 is a potent growth hormoine releasing peptide (GHRP). GHRPs are not simply surrogates of GHRH, instead GHRP-6 is an artificial activator of a separate newly discovered receptor called Growth Hormone Secretagogue Receptor (GHS-R). Soon Ghrelin was discovered, the endogenous ligand that binds to the GHS-R. Both Ghrelin and all the synthetic compounds such as GHRP-6 were termed "Growth Hormone Secretagogues" (GHSs).
 
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