Maple Side-by-side research comparison of growth hormone secretagogues and GHRH analogues: CJC-1295 (DAC and No DAC variants), Ipamorelin, and Tesamorelin. Covers receptor mechanisms, GH release profiles, selectivity differences, and research applications.
The GH Axis: Two Receptor Systems
Growth hormone release from anterior pituitary somatotrophs is controlled by two complementary receptor systems that operate through distinct mechanisms. Understanding this distinction is essential for evaluating secretagogue compounds:
Because these two systems converge on GH release through different intracellular pathways, they produce synergistic (not merely additive) effects when activated simultaneously. This is why CJC-1295 + Ipamorelin combinations are a major focus of secretagogue research.
Head-to-Head Comparison
| Parameter | CJC-1295 (No DAC) | CJC-1295 (DAC) | Ipamorelin | Tesamorelin |
|---|---|---|---|---|
| Target Receptor | GHRHR | GHRHR | GHS-R1a | GHRHR |
| Native Analogue | GHRH(1-29) | GHRH(1-29) | Ghrelin | GHRH(1-44) |
| Amino Acids | 29 (modified) | 29 + DAC conjugate | 5 (pentapeptide) | 44 (modified) |
| Half-Life | ~30 min | ~8 days (albumin-bound) | ~2 hours | ~26 min |
| GH Release Pattern | Pulsatile (preserves natural rhythm) | Tonic/sustained (elevated baseline) | Pulsatile (sharp, clean peaks) | Pulsatile |
| GH Selectivity | GH only | GH only | GH only (does NOT release cortisol, prolactin, or ACTH) | GH + IGF-1 axis |
| Cortisol/Prolactin | No effect | No effect | No effect (key differentiator from GHRP-6, hexarelin) | No significant effect |
| Appetite Stimulation | None | None | Minimal (unlike GHRP-6) | None |
| FDA Status | Research only | Research only | Research only | FDA approved (Egrifta, 2010) |
| Key Distinction | Short-acting GHRH, preserves pulsatility | Long-acting GHRH, continuous elevation | Cleanest GHS-R1a agonist available | Only FDA-approved GHRH analogue |
CJC-1295: DAC vs No DAC
CJC-1295 is a synthetic GHRH(1-29) analogue with four amino acid substitutions (Ala2, Gln8, Ala15, Leu27) that confer DPP-4 resistance. It exists in two distinct forms that produce fundamentally different GH release profiles:
CJC-1295 No DAC (Modified GRF 1-29)
Without the Drug Affinity Complex, CJC-1295 has a half-life of approximately 30 minutes. This short duration preserves the body’s natural pulsatile GH release pattern: each administration triggers a discrete GH pulse that rises and falls, mimicking physiological GHRH signaling. The pulsatile pattern is considered more physiologically relevant because GH receptor sensitivity is maintained through intermittent (not continuous) receptor activation.
CJC-1295 DAC
The Drug Affinity Complex (a reactive maleimidopropionic acid group) forms a covalent bond with serum albumin after injection, extending the half-life to approximately 8 days. This creates sustained, tonic GHRH receptor stimulation rather than discrete pulses. While this elevates average GH and IGF-1 levels more consistently, the loss of pulsatility raises research questions about GH receptor desensitization and feedback suppression with prolonged use.
Ipamorelin: The Selectivity Advantage
Ipamorelin’s primary research value is its selectivity. Among GHS-R1a agonists, it is the only compound that stimulates GH release without concurrent increases in cortisol, prolactin, or ACTH at standard research doses. This selectivity makes it the preferred tool for isolating GH-specific effects in research settings, since confounding hormonal changes (appetite stimulation from ghrelin mimicry, cortisol elevation from GHRP-6, prolactin release from hexarelin) are eliminated.
As a pentapeptide (Aib-His-D-2Nal-D-Phe-Lys-NH2), ipamorelin’s small molecular size contributes to its clean pharmacological profile. It binds GHS-R1a with high affinity but does not activate the receptor’s constitutive activity in the same manner as the larger hexapeptide secretagogues.
Tesamorelin: The Clinical Benchmark
Tesamorelin (GHRH(1-44) with a trans-3-hexenoic acid modification at the N-terminus) is the only GHRH analogue with FDA approval. Its approval for HIV-associated lipodystrophy (Egrifta, 2010) established clinical proof-of-concept for GHRH agonism as a therapeutic strategy. In the research context, tesamorelin’s published clinical data provides the strongest evidence base for GHRH-mediated effects on body composition, IGF-1 axis modulation, and visceral adipose tissue.
Synergy: GHRH + GHS-R1a Co-Activation
The combination of a GHRH agonist (CJC-1295) with a GHS-R1a agonist (Ipamorelin) is one of the most studied peptide combinations in secretagogue research. The rationale is straightforward: GHRH sets the pulse amplitude while ghrelin-mimetic signaling triggers the pulse. When both systems are activated simultaneously, GH release is synergistic because:
GHRH increases somatotroph cAMP via Gs coupling, priming the cell for maximum GH release. Ipamorelin increases intracellular calcium via Gq/PLC coupling, triggering exocytosis of GH-containing granules. The two pathways converge on secretory machinery through complementary second messengers, producing GH peaks larger than either agent alone.
| Combination | Mechanism | GH Pattern | Research Use Case |
|---|---|---|---|
| CJC-1295 No DAC + Ipamorelin | GHRHR + GHS-R1a synergy | Large pulsatile peaks | Acute GH pulse research, pulsatility studies |
| CJC-1295 DAC + Ipamorelin | Sustained GHRHR + GHS-R1a | Elevated baseline with pulses | Sustained IGF-1 elevation research |
| Ipamorelin alone | GHS-R1a only | Clean pulsatile peaks | Isolating GH-specific effects |
| CJC-1295 alone | GHRHR only | Moderate pulsatile peaks | GHRH pathway studies |
Research Products
Available at Maple Research Labs
All products include third-party COA verification and same-day Canadian shipping
CJC-1295 No DAC |
CJC-1295 DAC |
Ipamorelin 5MG |
Ipamorelin 10MG |
CJC-1295/Ipamorelin Blend |
Tesamorelin 5MG
Deep-Dive Research Pages
CJC-1295 (GHRH Agonist) Research | Full mechanism, DAC pharmacokinetics, synergy data
Ipamorelin Research | GHS-R1a selectivity, comparison with GHRP-6/hexarelin
Tesamorelin Research | FDA-approved GHRH analogue, clinical trial data
Frequently Asked Questions
What is the difference between CJC-1295 DAC and No DAC?
CJC-1295 No DAC (also called Modified GRF 1-29) has a half-life of about 30 minutes and produces discrete, pulsatile GH release that mimics natural physiology. CJC-1295 DAC includes a Drug Affinity Complex that bonds to serum albumin, extending the half-life to approximately 8 days and creating sustained, tonic GH elevation. The No DAC form preserves pulsatility; the DAC form maximizes sustained IGF-1 elevation. They serve different research purposes and are not interchangeable.
Why is ipamorelin considered the cleanest growth hormone secretagogue?
Ipamorelin selectively activates GHS-R1a to release growth hormone without stimulating cortisol, prolactin, or ACTH at standard research concentrations. Other GHS-R1a agonists like GHRP-6 stimulate appetite and can elevate cortisol, while hexarelin can increase prolactin. Ipamorelin’s selectivity makes it the preferred research tool when GH-specific effects need to be isolated from confounding hormonal changes.
Why combine CJC-1295 with Ipamorelin in research?
CJC-1295 (GHRH receptor agonist) and Ipamorelin (GHS-R1a agonist) activate two different receptor systems that converge on GH release through complementary intracellular signaling pathways. GHRH increases cAMP via Gs coupling, priming somatotrophs for maximum output. Ipamorelin increases intracellular calcium via Gq/PLC coupling, triggering secretory granule exocytosis. The result is synergistic GH release, with peaks larger than either compound alone.
Where can I buy growth hormone secretagogues for research in Canada?
Maple Research Labs supplies CJC-1295 (both DAC and No DAC variants), Ipamorelin (5MG and 10MG), a pre-blended CJC-1295/Ipamorelin combination, and Tesamorelin within Canada. All products include third-party purity verification via HPLC and mass spectrometry, batch-specific COAs, and same-day shipping. These compounds are supplied exclusively for in-vitro and preclinical research use.