Beginner Guide
What Are Growth Hormone Peptides?
A beginner guide to growth hormone peptides and the somatotropic axis, from hypothalamic signals to IGF-1 and tissue-level effects.
Growth Hormone Peptides in Plain Language
Growth hormone peptides are research compounds that interact with the somatotropic axis — the hormonal cascade that controls growth hormone production and its downstream effects. The system works like a relay:
- Step 1: The hypothalamus releases GHRH (growth hormone releasing hormone) → Sermorelin and Tesamorelin mimic this signal.
- Step 2: The pituitary gland releases GH in pulses → Ipamorelin amplifies these pulses through a different receptor.
- Step 3: GH tells the liver to produce IGF-1 → IGF1-LR3 is a modified version of this downstream effector.
- Step 4: GH and IGF-1 affect target tissues (muscle, bone, fat) → AOD-9604 isolates the fat-specific effect.
The OSYRIS GH category provides tools at every level of this cascade, allowing researchers to study GH biology from any angle.
What's in the OSYRIS GH Category
| Compound | Axis Level | What It Does |
|---|---|---|
| Sermorelin | Hypothalamic | Mimics GHRH (short-acting) |
| Tesamorelin | Hypothalamic | Mimics GHRH (DPP-IV resistant) |
| Ipamorelin | Pituitary | Selectively amplifies GH pulses |
| CJC/Ipamorelin Blend | Both | GHRH + GHRP synergy |
| IGF1-LR3 | Effector | Direct IGF-1 receptor activation |
| AOD-9604 | Fragment | Fat-specific GH fragment |
Where to Go Next
Featured Links
Get the full view of GHRH, GHRP, IGF-1, and GH-fragment research across the somatotropic axis.
Read → Shop Collection Growth Hormone CollectionBrowse the full GH-axis catalog, from Sermorelin and Tesamorelin to Ipamorelin, IGF1-LR3, and AOD-9604.
Browse → Beginner Guide What Are Research Peptides?Start with the broad primer on what peptides are, how they are studied, and why RUO context matters.
Read →Questions
Common Questions
Are these the same as HGH injections?
No. Secretagogues (Ipamorelin, Sermorelin) stimulate the pituitary to release GH naturally in pulses. HGH injections provide the hormone directly at a sustained level. Different patterns, different downstream effects.
What is a secretagogue?
A compound that stimulates a gland to release a hormone. GH secretagogues stimulate the pituitary gland to release growth hormone.
Why are there so many GH compounds?
Because GH biology involves multiple levels (hypothalamus → pituitary → liver → tissues). Different compounds target different levels.
What makes Ipamorelin special?
Selectivity. It releases GH without raising cortisol, prolactin, or aldosterone — side effects caused by older GH secretagogues.
What is IGF-1?
Insulin-like Growth Factor 1 — the downstream effector of GH. The liver produces IGF-1 in response to GH, and IGF-1 mediates many of GH's tissue effects.
Are these FDA approved?
Tesamorelin (Egrifta) has current FDA approval for a specific indication. Sermorelin had FDA approval (now discontinued). Others are research compounds only.
