Hexarelin is one of the growth-hormone-releasing peptides, notable for its
potency and for cardiac effects reported separately from its GH activity.
Chemical identity & structure.
Hexarelin is a synthetic hexapeptide (six amino acids) in the
growth-hormone-releasing-peptide (GHRP) family. Like the other GHRPs it is a
ghrelin mimetic — a synthetic agonist of the growth hormone secretagogue
receptor (GHS-R) rather than a GHRH analog.
Mechanism of action.
Hexarelin agonizes the GHS-R to stimulate a pituitary growth hormone pulse. It
is reported to be among the more potent GH secretagogues. Unlike the highly
selective ipamorelin, hexarelin is less selective and is reported to also raise
cortisol and prolactin to some degree. Separately, hexarelin has been studied
for direct cardiovascular effects that appear to involve the CD36 receptor
rather than the classic GHS-R/GH pathway.
Key research findings.
The literature documents reliable, strong GH-release stimulation, attenuation of
that response with continued exposure (desensitization), and a separate line of
preclinical cardiovascular research.
The research / citation base.
Hexarelin is not an approved drug. Its evidence base is early clinical
pharmacology and preclinical research. The cardiovascular findings are
preclinical and should not be read as established human therapy.
Human clinical trial data.
In the study by Maccario et al. (2002), six normal young men received
hexarelin 1.5 microg/kg s.c. two or three times daily, with 1 microg/kg i.v. at
the end of each 24-h sampling period; prior hexarelin administration in that
study blunted the GH response
(PubMed). The reported
desensitization with repeated exposure is a recurring theme in the pharmacology
literature.
Quality & sourcing notes.
A batch-specific COA with mass-spectrometry identity and HPLC purity is the
minimum bar. GHRP-family peptides are small and similar; confirm the COA
describes hexarelin specifically.
*Research-use note: Educational summary of published research. Hexarelin is not
an approved drug; this is research context only and not medical advice.*