CJC-1295 / Ipamorelin (No DAC)

This blend pairs two synthetic peptides that act at different receptors. The first is a substituted 29-residue analog of growth hormone-releasing hormone without the maleimide albumin-binding group of the DAC version; GRF(1-29) is the shortest N-terminal fragment of the 44-residue native factor retaining full activity, and it acts at the pituitary GHRH receptor, a G protein-coupled receptor of the secretin and vasoactive intestinal peptide family. The second is ipamorelin, the pentapeptide Aib-His-D-2-Nal-D-Phe-Lys-NH2, which acts instead at the ghrelin receptor.

CJC-1295 / Ipamorelin (No DAC) in the research literature

The GHRH receptor was cloned from rat pituitary mRNA, binds the releasing factor with high affinity and raises intracellular cAMP. GRF(1-29)-NH2 was reported to be equipotent with the full-length GRF(1-44)-NH2 in a rat pituitary bioassay with full receptor-binding affinity, and substituted analogs such as [Ala15]-GRF(1-29)-NH2 were described as superactive in that assay.

Ipamorelin engages a separate pathway. In primary rat pituitary cell culture it released growth hormone with potency similar to GHRP-6, and antagonist profiling indicated a GHRP-type receptor rather than the GHRH receptor. Earlier rat work on the GHRP hexapeptide series described a dual hypothalamic and pituitary site of action mediated by neither GHRH nor opiate receptors, establishing the two receptor systems as pharmacologically distinct.