Category

GHRH Analogs

GHRH receptor agonists — the other half of the growth-hormone axis from the GHRPs. All four act on the somatotroph the way endogenous growth hormone-releasing hormone does, so the release they produce still passes through the pituitary's own feedback. That is why comparative designs pair one of these with a GHS-R1a secretagogue instead of using either class on its own.

Sermorelin is the reference sequence: GHRH (1–29) amide, 3357.93 g/mol, the shortest fragment that keeps full receptor activity. CJC-1295 without DAC — the same molecule sold as Modified GRF 1-29 — is those 29 residues with four substitutions, D-Ala2, Gln8, Ala15 and Leu27, which block dipeptidyl-peptidase cleavage and methionine oxidation. It weighs 3367.93 g/mol, ten daltons more than sermorelin, and the ten daltons are the whole point: identical receptor, materially different stability. Tesamorelin goes the other way and keeps the full 44-residue hormone at 5135.86 g/mol with a trans-3-hexenoyl group on the N-terminal tyrosine; it is the one with visceral-adipose metabolism attached to it in the literature.

CJC-1295 with DAC is the decision point on this shelf. A lysine at position 30 carries a maleimidopropionamide group that adds covalently to cysteine-34 of serum albumin, giving 3647.28 g/mol before conjugation and an exposure window measured in days rather than minutes. That converts a pulsatile signal into a continuous one — which is what receptor-desensitisation and IGF-1-dynamics studies want, and what a design modelling endogenous release specifically does not — so the DAC and no-DAC forms are not interchangeable even though their receptor target is the same. All four ship as lyophilized powder in sealed vials: 2, 5 and 10 mg for sermorelin and both CJC-1295 forms, 5, 10 and 20 mg for tesamorelin. Vials that pre-combine a GHRH analogue with a GHRP are stocked separately under growth-hormone blends.