GH
Axis

Growth-hormone-axis research uses two complementary classes of peptides. GHRH analogues — sermorelin, tesamorelin and CJC-1295 with or without DAC — act on the pituitary GHRH receptor. Ghrelin-receptor (GHS-R1a) agonists — ipamorelin, GHRP-2, GHRP-6 and hexarelin — trigger GH release through a separate pathway, and they differ in selectivity for cortisol, prolactin and appetite signalling.

IGF-1 variants such as IGF-1 LR3 and IGF-1 DES, along with PEG-MGF, are used in cell-culture and muscle-biology research downstream of GH. Researchers often compare the two upstream classes directly, which is why we keep a dedicated comparison guide.