CJC-1295 without DAC, chemically identified as Modified GRF 1-29, is a synthetic 29-amino acid tetrasubstituted peptide analog of growth hormone-releasing hormone (GHRH). It is widely investigated in preclinical research models to evaluate selective GHRH receptor stimulation, physiological growth hormone dynamics, and downstream signaling cascades without the prolonged half-life imparted by drug affinity complex technology.
CJC-1295 without DAC, chemically identified as Modified GRF 1-29, is a synthetic 29-amino acid tetrasubstituted peptide analog of growth hormone-releasing hormone (GHRH). It is widely investigated in preclinical research models to evaluate selective GHRH receptor stimulation, physiological growth hormone dynamics, and downstream signaling cascades without the prolonged half-life imparted by drug affinity complex technology.
CJC-1295 without DAC (also known as Modified GRF 1-29) is a synthetic 29-amino acid peptide analog of growth hormone-releasing hormone (GHRH). It selectively binds to GHRH receptors on pituitary somatotropes to stimulate pulsatile growth hormone (GH) secretion and downstream insulin-like growth factor 1 (IGF-1) elevation without extending plasma half-life through albumin conjugation.
In physiological systems, native GHRH (a 44-amino acid peptide) exhibits an exceptionally short biological half-life—typically under 10 minutes—due to rapid cleavage by circulating enzymes such as dipeptidyl peptidase IV (DPP-IV). To mitigate this enzymatic instability in experimental environments, molecular researchers designed Modified GRF 1-29 by substituting four specific amino acids within the core 1-29 bioactive region. When researchers evaluate cjc-1295 without dac in vitro or in animal models, they are studying a modified peptide structure optimized for resistance to enzymatic inactivation while preserving natural somatotrope receptor binding dynamics.
Because this variant lacks the Drug Affinity Complex (DAC)—a maleimido derivative reactive group that covalently binds to serum albumin—its biological clearance remains transient. This fundamental property makes it an indispensable tool for scientific investigators seeking to model discrete, pulsatile bursts of GH secretion rather than continuous, baseline GH elevation in endocrine and cellular research.
The molecular architecture of CJC-1295 without DAC is derived from the N-terminal 29-amino acid chain of endogenous GHRH, which represents the minimal functional sequence required to maintain full biological affinity at the GHRH receptor. The chemical formula of this tetrasubstituted peptide is C152H252N44O42, featuring a molecular weight of approximately 3367.2 Da.
The exact sequence of CJC-1295 without DAC is expressed as: 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. Four deliberate amino acid modifications differentiate this research compound from natural GRF 1-29: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27.
The inclusion of D-alanine at position 2 is structurally critical because DPP-IV primarily targets the peptide bond between the second and third amino acid residues. Substitution with the D-isomer prevents enzymatic recognition, significantly expanding the half-life of the free peptide in bioassays from minutes to approximately 30 minutes. The additional substitutions at positions 8, 15, and 27 preserve structural integrity against oxidation and thermal degradation, yielding a highly stable ligand for advanced research applications.
At the cellular level, CJC-1295 without DAC operates as a selective agonist at the GHRH receptor (GHRHR), a class B G-protein-coupled receptor predominantly localized on the cell surface of anterior pituitary somatotropes. Upon ligand binding, the receptor undergoes a conformational change that activates the stimulatory G-protein sub-unit (Gαs).
This intracellular activation triggers adenylyl cyclase, escalating the conversion of adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP). Rising cAMP concentrations activate protein kinase A (PKA), which subsequently phosphorylates specific transcription factors, including cAMP response element-binding protein (CREB). This signaling cascade upregulates the transcription of the growth hormone gene and stimulates L-type voltage-gated calcium channels, prompting extracellular calcium influx and triggering exocytosis of stored GH secretory vesicles.
Preclinical data indicate that CJC-1295 without DAC maintains the physiological feedback loops governing the somatotropic axis. Because it does not continuously occupy the receptor over extended periods, somatostatin (growth hormone-inhibiting hormone) can periodically override GHRH signaling. This allows research models to display normal, physiological GH pulsing rather than receptor down-regulation or pathologically flattened GH elevation, as detailed in our comprehensive research library.
To accurately structure preclinical protocols, researchers must delineate the functional differences between various secretagogues within the GHRH analog class. The presence or absence of the Drug Affinity Complex fundamentally alters pharmacokinetics and receptor kinetics in animal models.
When comparing GHRH analogs, CJC-1295 with DAC contains a Lys(Maleimidopropionyl) modification that enables irreversible covalent binding to endogenous serum albumin, extending its biological half-life to several days and producing sustained, tonic growth hormone release. Conversely, cjc-1295 without dac exhibits an elimination half-life of approximately 30 minutes, producing rapid, peak-and-trough GH pulses. In comparative experimental designs, researchers also analyze Sermorelin, an unmodified 1-29 GHRH fragment that displays rapid enzymatic clearance (half-life of 8–12 minutes), and Ipamorelin, a selective ghrelin receptor agonist that operates via a distinct, complementary secretagogue pathway.
The following matrix summarizes key structural and operational parameters among these common research compounds:
A major area of investigation within neuroendocrine literature is the co-administration of GHRH analogs alongside Growth Hormone Releasing Peptides (GHRPs) or ghrelin receptor (GHSR-1a) agonists. While GHRH analogs activate the cAMP/PKA pathway via GHRHR, GHRPs signal through the phospholipase C (PLC) / inositol trisphosphate (IP3) pathway.
In cell culture and rodent models, simultaneous activation of both the GHRHR and GHSR-1a pathways generates a synergistic release of growth hormone that significantly exceeds the additive total of either compound evaluated in isolation. Co-application suppresses endogenous somatostatin tone while concurrently magnifying somatotrope vesicle release.
Laboratory designs frequently pair CJC-1295 without DAC with selective growth hormone secretagogues such as Ipamorelin or GHRP-2 to evaluate maximum somatotropic output without causing excessive cortisol or prolactin secretion. Further information regarding dual-pathway secretagogue protocols is available in our analysis of GHRH analogs and mechanisms.
In animal models, administration of CJC-1295 without DAC results in rapid, measurable elevations in plasma growth hormone concentrations. Rodent studies demonstrate that peak serum GH concentrations are typically observed within 15 to 30 minutes post-application, followed by a gradual return to baseline as the unbound peptide undergoes systemic clearance.
Repeated pulsatile exposure to CJC-1295 without DAC in preclinical subjects stimulates hepatic expression and secretion of insulin-like growth factor 1 (IGF-1) and its primary circulating carrier protein, IGFBP-3. Because IGF-1 synthesis is driven by cumulative somatotropic activity, studies demonstrate elevated circulating IGF-1 concentrations even when individual GH spikes are transient.
Data from non-human primate and rodent bioassays suggest that the short half-life of CJC-1295 without DAC prevents permanent desensitization of somatotrope GHRH receptors. This preserves natural receptor resensitization cycles between secretagogue spikes, ensuring consistent, repeatable physiological responses across longitudinal research timelines.
Due to its capacity to sustain physiological GH and IGF-1 signaling cascades, CJC-1295 without DAC is extensively utilized across preclinical studies evaluating tissue regeneration, musculoskeletal preservation, and cellular metabolism.
In animal models of musculoskeletal injury, GH-induced IGF-1 elevation enhances collagen synthesis within connective tissue structures, including tendons and ligaments. Preclinical research indicates accelerated satellite cell proliferation and local protein translation in skeletal muscle tissue following controlled somatotropic stimulation, as outlined in our report on Ipamorelin mechanisms.
Additionally, secretagogue-mediated GH surges modulate metabolic pathways in animal models by promoting lipolysis in visceral adipocytes through upregulation of hormone-sensitive lipase (HSL). Researchers monitoring substrate utilization note enhanced free fatty acid mobilization and improved nitrogen retention, rendering CJC-1295 without DAC a valuable research tool for investigating metabolic homeostasis and body composition dynamics.
To preserve chemical stability and prevent pre-assay degradation, lyophilized CJC-1295 without DAC must be reconstituted using strict aseptic technique within a certified laboratory environment.
Standard reconstitution procedures involve the gradual addition of sterile bacteriostatic water (0.9% benzyl alcohol) down the inner glass wall of the vial. Direct stream impact onto the lyophilized cake should be avoided to prevent mechanical shear stress on the peptide backbone. The vial should be gently swirled in a circular motion until the lyophilized matrix is fully dissolved; shaking or vigorous agitation must be avoided as it can induce protein aggregation or denature delicate secondary structures.
Reconstituted solutions should be clear and free of particulate matter. Aliquoting the solution into single-use microcentrifuge tubes immediately following reconstitution minimizes degradation associated with repeated freeze-thaw cycles during multi-day experimental runs.
In its original, lyophilized state, CJC-1295 without DAC exhibits high stability when maintained under controlled low-temperature conditions. Upon receipt in the laboratory, lyophilized vials should be stored at -20°C for short-to-medium duration research or at -80°C for long-term storage, protected from direct light exposure.
Lyophilized cakes stored at -20°C typically maintain chemical stability and structural integrity for up to 24 months. Exposure to ambient temperatures during short-term transit does not compromise structural viability provided the product is returned to sub-zero storage upon arrival.
Once reconstituted in bacteriostatic water, liquid solutions must be kept refrigerated at 2°C to 8°C and utilized within 21 to 28 days. Avoid storing reconstituted peptide solutions in frost-free freezers, as fluctuating temperature cycles accelerate peptide degradation through thermal cycling.
To ensure high experimental reproducibility, research facilities require strict quality control verification for every lot of CJC-1295 without DAC. Reliable analytical assessment relies on a combination of chromatographic, mass spectroscopic, and biological assays.
Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) is the primary technique used to assess chemical purity. PX1 Research mandates that every batch achieves greater than 98% purity, confirmed by sharp, single-peak chromatographic profiles free from truncated sequences or synthesis impurities. Electrospray Ionization Mass Spectrometry (ESI-MS) is concurrently performed to verify exact molecular mass, confirming correct amino acid assembly.
Because bacterial contaminants can induce unwanted inflammatory signaling in cellular and animal models, comprehensive testing includes Chromogenic Limulus Amebocyte Lysate (LAL) assays for endotoxin quantification. PX1 Research enforces stringent limits, ensuring endotoxin levels remain below 0.01 EU/μg to guarantee uncompromised, research-grade reagents.
High-purity reagents are essential for eliminating confounding variables in scientific experimentation. Low-grade research compounds containing synthesis artifacts, TFA residues, or bacterial endotoxins undermine experimental validity and produce inconsistent assay data.
PX1 Research manufactures all compounds in state-of-the-art, GMP-compliant facilities located within the United States. Operating through an ISO 17025 accredited laboratory network, every production lot undergoes rigorous third-party testing, with lot-specific Certificates of Analysis (COAs) containing raw RP-HPLC chromatograms and mass spectra accessible to verification teams.
Laboratories seeking consistent, high-purity GHRH analogs can procure verified cjc-1295 without dac directly through our catalog. For institutional procurement, volume pricing, and institutional supply arrangements, research teams can review our wholesale account portal or explore our complete catalog of research peptides.
What is the exact chemical distinction between CJC-1295 without DAC and CJC-1295 with DAC?
CJC-1295 without DAC (Modified GRF 1-29) consists solely of a 29-amino acid tetrasubstituted peptide sequence with a half-life of approximately 30 minutes. CJC-1295 with DAC incorporates a Drug Affinity Complex (a maleimide derivative) attached to a lysine linker, allowing the molecule to bind covalently to serum albumin in vivo and extending its biological half-life to several days.
Why is CJC-1295 without DAC frequently referred to as Modified GRF 1-29?
The name 'Modified GRF 1-29' accurately describes the chemical structure: it is the 1-29 amino acid fragment of Growth Hormone Releasing Factor modified at four positions (D-Ala2, Gln8, Ala15, Leu27) to resist enzymatic degradation by DPP-IV while omitting the DAC structure.
What receptor pathway does CJC-1295 without DAC target in laboratory assays?
CJC-1295 without DAC acts as a selective agonist at the growth hormone-releasing hormone receptor (GHRHR) on pituitary somatotropes. Receptor binding activates the Gαs protein/cAMP/PKA intracellular cascade, promoting exocytosis of growth hormone storage vesicles.
How should lyophilized CJC-1295 without DAC be stored upon receipt in the laboratory?
Lyophilized CJC-1295 without DAC should be stored in a dry, dark environment at -20°C for short-to-medium term storage, or at -80°C for long-term preservation to maintain structural integrity and prevent hydrolytic cleavage.
What solvent is recommended for reconstituting CJC-1295 without DAC for bioassays?
For multi-use laboratory applications requiring microbial inhibition, sterile bacteriostatic water (0.9% benzyl alcohol) is recommended. For short-term in vitro assays where benzyl alcohol could interfere with cell viability, sterile 0.9% sodium chloride or phosphate-buffered saline (PBS) may be utilized.
How does CJC-1295 without DAC synergize with GHRPs in preclinical models?
CJC-1295 without DAC activates the GHRHR via the cAMP/PKA pathway, while GHRPs (such as Ipamorelin) stimulate the GHSR-1a receptor via the IP3/PLC pathway. Concurrent activation of both pathways yields a synergistic enhancement of GH release that exceeds the sum of individual secretagogue applications.
What analytical methods verify the purity and identity of CJC-1295 without DAC from PX1 Research?
Every lot undergoes Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) to confirm purity levels exceeding 98%, Electrospray Ionization Mass Spectrometry (ESI-MS) to verify exact molecular mass, and Chromogenic LAL assays to quantify endotoxin levels.
What endotoxin thresholds are enforced for research-grade CJC-1295 without DAC?
PX1 Research enforces a strict endotoxin threshold of less than 0.01 EU/μg for CJC-1295 without DAC, ensuring that research reagents do not induce non-specific inflammatory responses or confound cell culture and animal model data.
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