Ipamorelin 10 mg

Ipamorelin 10 mg research-grade lyophilized peptide powder in a glass vial. Ipamorelin is a selective growth hormone secretagogue and ghrelin/GHS-R agonist studied in models of growth hormone secretion, endocrine signaling and ghrelin-pathway research.

Research Overview

Ipamorelin is a synthetic pentapeptide investigated as a selective agonist of the ghrelin/growth hormone secretagogue receptor (GHS-R). In experimental systems it is used as a tool compound to study growth hormone secretion, pituitary responsiveness and ghrelin-pathway signaling without broad off-target receptor activation.

Primary Research Areas

• Growth hormone (GH) secretion: models examining pulsatile GH release, pituitary sensitivity and GHS-R–mediated signaling [1,2].
• Ghrelin / GHS-R pathways: research on selective ghrelin receptor agonism, downstream cascades and endocrine network interactions [1,7].
• Endocrine & metabolic models: studies of hypothalamic–pituitary axes, energy-balance signaling and hormone-regulation frameworks [1,5].
• Gastrointestinal motility research: experimental systems exploring ghrelin-related effects on GI motility and smooth-muscle activity [6].
• More body fat, not less: twice-daily injections raised body weight about 15% within two weeks in mice and increased fat-pad weight relative to body weight, in both growth-hormone-deficient and normal animals, with more food eaten. Growth hormone itself did the opposite and cut relative fat mass. In mice the fat came on without growth hormone doing it [5].
• Bigger bones, not denser ones: female rats given 0.5 mg/kg a day for 12 weeks gained bone mineral content, but once their extra body weight was allowed for the density had not changed: the bones had simply grown larger. That is not the denser bone that resists fracture, and it has never been measured in people [3].
• Muscle and bone lost to steroids: female rats on three months of methylprednisolone lost calf-muscle force and bone formation; 100 µg/kg of ipamorelin three times a day restored the maximum tetanic tension of the calf and raised the rate of new bone at the periosteum four-fold against the steroid alone. This is rats on a heavy steroid dose [4].
• Cortisol and prolactin left alone: in conscious pigs ipamorelin released growth hormone without moving FSH, LH, prolactin or TSH, and without the rise in ACTH and cortisol that GHRP-6 and GHRP-2 both caused. That held at doses more than 200 times the one needed for growth hormone, and it was measured in pigs, not people [1].
• Gut and skin pain in rats: rats made hypersensitive in the colon with dilute acetic acid had fewer abdominal contractions when the colon was distended after intravenous ipamorelin, and pulled the paw away less from a calibrated filament. A ghrelin-receptor blocker abolished both effects. It dulls pain as well as moving the gut, in rats [7].
• Weight loss during chemotherapy: ferrets given cisplatin lost weight and ate less; ipamorelin at 1–3 mg/kg did nothing for the vomiting but cut the weight loss in the later phase by roughly 24%. Small animals, one chemotherapy drug, and the appetite effect behind it is the same mechanism that added body fat in mice [8].

References

1. Raun K, Hansen BS, Johansen NL, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552-61. PMID 9849822. doi:10.1530/eje.0.1390552
2. Gobburu JV, Agersø H, Jusko WJ, et al. Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. 1999;16(9):1412-6. PMID 10496658. doi:10.1023/a:1018955126402
3. Svensson J, Lall S, Dickson SL, et al. The GH secretagogues ipamorelin and GH-releasing peptide-6 increase bone mineral content in adult female rats. J Endocrinol. 2000;165(3):569-77. PMID 10828840. doi:10.1677/joe.0.1650569
4. Andersen NB, Malmlöf K, Johansen PB, et al. The growth hormone secretagogue ipamorelin counteracts glucocorticoid-induced decrease in bone formation of adult rats. Growth Horm IGF Res. 2001;11(5):266-72. PMID 11735244. doi:10.1054/ghir.2001.0239
5. Lall S, Tung LY, Ohlsson C, et al. Growth hormone (GH)-independent stimulation of adiposity by GH secretagogues. Biochem Biophys Res Commun. 2001;280(1):132-8. PMID 11162489. doi:10.1006/bbrc.2000.4065
6. Beck DE, Sweeney WB, McCarter MD. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis. 2014;29(12):1527-34. PMID 25331030. doi:10.1007/s00384-014-2030-8
7. N Mohammadi E, Louwies T, Pietra C, et al. Attenuation of Visceral and Somatic Nociception by Ghrelin Mimetics. J Exp Pharmacol. 2020;12:267-274. PMID 32801950. doi:10.2147/JEP.S249747
8. Lu Z, Ngan MP, Liu JYH, et al. The growth hormone secretagogue receptor 1a agonists, anamorelin and ipamorelin, inhibit cisplatin-induced weight loss in ferrets: Anamorelin also exhibits anti-emetic effects via a central mechanism. Physiol Behav. 2024;284:114644. PMID 39043357. doi:10.1016/j.physbeh.2024.114644