Hexarelin — pharmacology
Molecular targets, mechanism of action, pharmacokinetics and interactions as characterised in humans.
§2Pharmacology
§2.1Molecular targets
Table 2. Molecular targets recorded for Hexarelin, with the character of the interaction and the potency where the Institute holds it.
| Target | Interaction | Note |
|---|---|---|
| Growth hormone secretagogue receptor (GHSR-1a) | Agonist | Potent but non-selective — also raises cortisol and prolactin |
| CD36 | Ligand | A distinct receptor interaction reported in cardiac tissue and proposed as the basis of preclinical cardioprotective effects independent of growth hormone |
§2.2Mechanism of action
Hexarelin is a potent ghrelin receptor agonist producing marked growth-hormone release. Unlike ipamorelin it also stimulates adrenocorticotropin, cortisol and prolactin, which the Institute regards as a material disadvantage rather than a neutral difference. A separate body of preclinical work describes CD36-mediated cardioprotective effects independent of the growth-hormone axis; this has not been tested in humans.[1,2]
§2.3Pharmacokinetics
- Terminal half-life
- ≈55 min
- Time to maximum concentration
- ≈15–30 min (subcutaneous)
- Volume of distribution
- not published
- Plasma protein binding
- not published
- Clearance
- not published
- Bioavailability
- low intranasally (approximately 4 %)
Proteolytic degradation. Tachyphylaxis of the growth-hormone response develops over weeks of continuous administration, which is documented and clinically important.
§2.4Interactions
- Not characterised
References cited on this page
References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.
- Raun K, Hansen BS, Johansen NL, Thøgersen H, Madsen K, Ankersen M, Andersen PH. Ipamorelin, the first selective growth hormone secretagogue. European Journal of Endocrinology 1998;139(5):552–561. doi:10.1530/eje.0.1390552 · PMID 9849822
- Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. Journal of Clinical Endocrinology & Metabolism 2006;91(3):799–805. doi:10.1210/jc.2005-1536 · PMID 16352683
Identifiers are reproduced only where the Institute holds them. Where a digital object identifier or PubMed identifier is not shown, the Institute has recorded the journal and year and has not constructed an identifier.