The GH and IGF-1 axis

One receptor upstream, a cascade downstream

CJC-1295 works one step upstream of growth hormone. It acts on the pituitary GHRH receptor, prompting your own gland to release growth hormone. That released GH then acts on tissues directly and drives the liver to make IGF-1, the hormone through which much of GH's growth signal was classically thought to run.

This unit maps the whole axis: where the receptor sits, how the signal runs inside a pituitary cell, how the liver relays it into IGF-1, and how the body feeds back to keep the system in check. Understanding this upstream position is the key difference from injecting growth hormone itself.