Sermorelin is a synthetic 29-amino acid peptide representing the biologically active N-terminal fragment of endogenous growth hormone-releasing hormone (GHRH 1-29). It binds and activates the GHRH receptor on somatotroph cells in the anterior pituitary, stimulating the synthesis and pulsatile secretion of endogenous GH. Unlike exogenous GH administration, sermorelin preserves the natural feedback mechanisms of the GH axis — GH release remains subject to hypothalamic somatostatin regulation, maintaining a physiological pulse pattern. It has been studied as a means of restoring age-related GH decline while respecting the body’s own regulatory architecture.