Chemistry and structure

A defined 29-residue fragment that carries the whole GHRH signal

Native GHRH is 44 amino acids long, but nearly all of its receptor-activating power lives in the first 29. Sermorelin is that fragment, capped with a C-terminal amide, made cleanly by solid-phase synthesis.

This unit walks the sequence, the structure that binds the receptor, and the single chemical weakness, rapid DPP-IV cleavage, that sets sermorelin apart from the longer-acting analogs.