The GH StackCJC-1295 + Ipamorelin Dual-Receptor Guide — QSC Peptides

Pituitary somatotroph cells express two distinct GH-stimulating receptor systems operating in parallel:

• GHRH receptor (GHRHR): Gs-coupled, activates adenylyl cyclase → cAMP → PKA → GH gene transcription and granule priming
• Ghrelin receptor (GHSR-1a): Gq-coupled, activates PLC → IP3 → Ca²⁺ → GH granule exocytosis

These two pathways are mechanistically independent — they use different second messengers (cAMP vs Ca²⁺) and drive different steps of GH secretion (synthesis/priming vs exocytosis). Activating both simultaneously produces additive to synergistic GH pulse amplification, exceeding what either compound alone can achieve.

CJC-1295 (No DAC) — GHRHR Component

CJC-1295 (Modified GRF 1-29) is the GHRHR agonist in the stack. With a ~30 minute half-life, it produces a clean pulsatile GHRHR activation, driving GH gene transcription and expanding the releasable GH granule pool in somatotrophs. It also amplifies pituitary responsiveness by upregulating GH synthesis between pulses.

Ipamorelin — GHSR-1a Component

Ipamorelin is the GHSR-1a agonist. It triggers the exocytotic release of the GH granules primed by CJC-1295, and additionally suppresses hypothalamic somatostatin tone — removing the brake on GH secretion and amplifying the GH pulse further. Its exceptional selectivity (no cortisol, prolactin, or appetite effects) keeps the research environment clean.

The Synergistic Effect

The sequential logic: CJC-1295 builds the granule pool and drives GH synthesis (GHRHR pathway); Ipamorelin triggers the release of that pool and removes somatostatin inhibition (GHSR-1a pathway). The result is a GH pulse substantially larger than either compound alone — the rationale for the QSC Peptides pre-blended GH Stack vial.