CJC-1295 No DAC, commonly designated as Modified GRF 1-29, is a synthetic 29-amino-acid peptide derivative of growth hormone-releasing hormone (GHRH). Designed for specialized in vitro and preclinical research, this GHRH analog stimulates pulsatile growth hormone secretion by binding to the pituitary GHRH receptor. Laboratory investigators utilize this compound to analyze somatotropic signaling, IGF-1 activation, and tissue regeneration pathways.
CJC-1295 No DAC, commonly designated as Modified GRF 1-29, is a synthetic 29-amino-acid peptide derivative of growth hormone-releasing hormone (GHRH). Designed for specialized in vitro and preclinical research, this GHRH analog stimulates pulsatile growth hormone secretion by binding to the pituitary GHRH receptor. Laboratory investigators utilize this compound to analyze somatotropic signaling, IGF-1 activation, and tissue regeneration pathways.
CJC-1295 No DAC (Modified Growth Hormone Releasing Factor 1-29) is a synthetic peptide modified from the native GHRH (1-29) sequence. Native GHRH contains 44 amino acids, but biological activity is maintained in the initial 29-amino-acid chain known as Sermorelin. To enhance metabolic stability against enzymatic cleavage, Mod GRF 1-29 incorporates four specific amino acid substitutions at positions 2, 8, 15, and 27 (specifically Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg-NH2).
The designation 'No DAC' explicitly indicates the absence of the Drug Affinity Complex (Maleimidopropionic acid linker), a chemical modification found in CJC-1295 DAC that binds to circulating serum albumin. Without the DAC motif, CJC-1295 No DAC exhibits a half-life of approximately 30 minutes in plasma, closely mimicking physiological, pulsatile growth hormone (GH) release patterns observed in mammalian models. Researchers evaluating pituitary secretagogues often select Mod GRF 1-29 to maintain discrete GH release peaks without causing continuous basal elevation.
The primary vulnerability of native GHRH(1-29) in laboratory media and biological plasma is rapid cleavage by endogenous dipeptidyl peptidase IV (DPP-IV), which degrades the peptide at the Ala2 site. In Mod GRF 1-29, D-alanine substitution at position 2 renders the peptide resistant to DPP-IV enzymatic inactivation.
Additional substitutions—glutamine at position 8, alanine at position 15, and leucine at position 27—further protect the alpha-helical secondary structure against oxidative and enzymatic degradation. These chemical modifications significantly extend plasma stability compared to unmodified GHRH(1-29) without converting the peptide into a continuous-release agent. For comparative studies regarding structural stability and plasma half-life extensions, researchers frequently review our detailed guide on GHRH analogs and secretagogue kinetics.
Mod GRF 1-29 functions as a selective agonist at the GHRH receptor (GHRHR), a class B G-protein-coupled receptor located primarily on somatotropes within the anterior pituitary gland. Upon ligand binding, GHRHR undergoes a conformational shift that stimulates membrane-bound adenylyl cyclase via the Gαs subunit.
Activation of adenylyl cyclase catalyzes the conversion of intracellular ATP to cyclic adenosine monophosphate (cAMP). Elevated cAMP levels activate protein kinase A (PKA), leading to the phosphorylation of transcription factors such as CREB and opening L-type voltage-gated calcium channels. Influx of extracellular calcium triggers exocytosis of stored growth hormone vesicles into extracellular fluid. In vitro assays demonstrate that Mod GRF 1-29 preserves endogenous negative feedback loops governed by somatostatin, maintaining natural pulsatile signaling dynamics.
Preclinical studies evaluating CJC-1295 No DAC in rodent and non-human primate models report dose-dependent elevations in circulating growth hormone levels followed by downstream induction of insulin-like growth factor 1 (IGF-1) transcript expression in hepatic tissue.
Because Mod GRF 1-29 maintains a transient half-life, the resulting GH pulses induce hepatic IGF-1 release without causing desensitization of the GHRH receptor. In vitro rodent models show that intermittent exposure to GHRH analogs preserves receptor density and response fidelity over extended experimental durations. Researchers interested in broader somatotropic axis modeling often cross-reference these findings in our research library hub.
Growth hormone and IGF-1 signaling cascades play central roles in cellular proliferation, protein translation, and extracellular matrix remodeling. In preclinical wound healing and musculoskeletal injury models, activation of the GHRH receptor has been linked to increased collagen synthesis, enhanced satellite cell activation in skeletal muscle, and accelerated fibroblast migration.
In vitro cultures of chondrocytes and osteoblasts exposed to GHRH analogs exhibit elevated markers of matrix deposition and mineral accumulation. Researchers investigating connective tissue recovery models often pair GHRH secretagogues with extracellular matrix repair compounds like BPC-157 or TB-500 to evaluate synergistic tissue regeneration pathways.
A major focus of laboratory investigations into growth factor dynamics is the synergistic interaction between GHRH analogs and Growth Hormone Releasing Peptides (GHRPs) or ghrelin receptor agonists. While Mod GRF 1-29 acts specifically on the GHRH receptor, ghrelin mimetic compounds operate via the growth hormone secretagogue receptor (GHS-R1a).
Co-administration of GHRH and GHS-R1a agonists in animal models yields a supra-additive response in pituitary GH release. The dual activation inhibits somatostatin signal transduction while simultaneously amplifying cAMP-dependent secretory pathways. Experimental setups exploring this dual-receptor mechanism regularly incorporate Ipamorelin or GHRP-2 alongside Mod GRF 1-29 to measure peak amplitude versus total area under the serum concentration curve.
Selecting the appropriate somatotropic agent depends on the precise physiological parameter under investigation. Researchers evaluating short-acting, pulsatile GHRH activity utilize CJC-1295 No DAC, whereas studies requiring persistent, sustained baseline GH elevations utilize CJC-1295 DAC.
When compared to unmodified Sermorelin, Mod GRF 1-29 offers superior enzymatic resistance and a longer functional window in culture media. Conversely, selective ghrelin receptor agonists like Ipamorelin stimulate GH release through independent intracellular signaling networks without altering plasma GHRH concentrations. Understanding these functional differences enables precise experimental design across metabolic, endocrine, and tissue recovery studies.
Lyophilized CJC-1295 No DAC should be stored upon receipt at -20°C or -80°C for long-term stability. The peptide powder is susceptible to degradation from moisture, temperature fluctuations, and repeated freeze-thaw cycles. Prior to opening, vials should be allowed to equilibrate to room temperature to prevent moisture condensation inside the container.
Reconstitution should be performed using bacteriostatic water or sterile standard laboratory diluents under a laminar flow hood. Gently introduce the solvent along the inner glass wall of the vial and allow the cake to dissolve without aggressive vortexing, which can denature delicate peptide chains. Following reconstitution, liquid aliquots must be maintained at 2°C to 8°C and used within defined experimental timeframes. Detailed protocols for liquid handling are available in our guide on peptide reconstitution protocols.
Reliable research outcomes require absolute purity and lot-to-lot consistency. PX1 Research subjects every batch of synthesized peptides to rigorous analytical testing in independent, ISO 17025 accredited facilities. Quality parameters are verified through high-performance liquid chromatography (RP-HPLC) to confirm structural purity exceeding 99%.
Mass spectrometry (MS) analysis verifies the exact molecular mass (C152H252N44O42, theoretical MW 3367.9 g/mol), ensuring the absence of truncated sequences or synthesis byproducts. Furthermore, chromogenic LAL assays are conducted to ensure endotoxin limits remain strictly under 0.5 EU/mg. Every product shipment includes a batch-specific Certificate of Analysis (COA) for full experimental compliance.
PX1 Research provides academic institutions, biotechnology organizations, and independent scientific laboratories with premium research compounds manufactured under strict quality standards. All products are manufactured in GMP-compliant facilities within the United States, supporting reproducible experimental models.
Orders are dispatched with same-day shipping (Monday through Friday) directly from specialized distribution centers in California and Arizona. Scientific institutions requiring high-volume supplies or specialized batch documentation can apply for institutional procurement terms via our wholesale lab accounts portal.
What is the key difference between CJC-1295 No DAC and CJC-1295 DAC?
CJC-1295 No DAC (Mod GRF 1-29) lacks the Drug Affinity Complex (DAC) modification. As a result, it has a short half-life of ~30 minutes and promotes pulsatile GH release, whereas CJC-1295 DAC binds serum albumin, extending its half-life to several days and producing continuous baseline GH elevation.
What is the molecular weight and formula of Mod GRF 1-29?
Modified GRF 1-29 has a chemical formula of C152H252N44O42 and a molecular weight of approximately 3367.9 Da.
How does CJC-1295 No DAC function in vitro?
It acts as a selective GHRH receptor agonist, activating the Gαs/adenylyl cyclase/cAMP/PKA pathway in pituitary somatotropes to induce growth hormone exocytosis.
How should CJC-1295 No DAC be stored in the laboratory?
Lyophilized powder should be stored at -20°C or -80°C. Reconstituted solution should be kept refrigerated at 2°C to 8°C and protected from light and agitation.
What analytical testing is performed on PX1 Research compounds?
Every lot undergoes third-party ISO 17025 testing including RP-HPLC for purity (>99%), Mass Spectrometry for identity confirmation, and LAL testing for endotoxins (<0.5 EU/mg).
Why is Mod GRF 1-29 often paired with Ipamorelin in research models?
Mod GRF 1-29 targets the GHRH receptor, while Ipamorelin targets the ghrelin receptor (GHS-R1a). Co-activation produces a synergistic release of GH greater than either compound alone.
Are PX1 Research compounds suitable for human clinical use?
No. All products sold by PX1 Research are strictly for laboratory research, in vitro assays, and preclinical animal studies. They are not intended for human consumption or therapeutic use.
Where are PX1 Research products manufactured and shipped from?
PX1 Research peptides are manufactured in USA-based GMP-compliant facilities and shipped same-day (M-F) from logistics hubs in California and Arizona.
All products are sold strictly for laboratory and research use only. Not for human or veterinary use, diagnosis, treatment or consumption. Statements have not been evaluated by the FDA.