CJC No DAC in In Vitro Models: Research Context

What is CJC No DAC studied for in in vitro models?

CJC No DAC is a synthetic peptide studied in research as an analog of growth hormone releasing hormone (GHRH), engineered to resist enzymatic degradation relative to the native hormone. It is catalogued under CAS number 863288-34-0 with a molecular formula of C₁₅₂H₂₅₂N₄₄O₄₂ and a molecular weight of 3367.9 Da. The compound is supplied as a lyophilized powder for laboratory research and is intended solely for research purposes, not for human use.

In vitro, CJC No DAC is studied primarily in pituitary cell culture models as a tool for probing GHRH receptor (GHRHR) signaling with a stabilized, longer-acting-in-solution analog rather than the native, rapidly degraded hormone. Because it lacks the Drug Affinity Complex (DAC) — an albumin-binding modification present in a related analog, CJC-1295 with DAC — its in vitro behavior more closely resembles that of unmodified GHRH fragments, which makes it a useful reference compound for isolating receptor pharmacology from the pharmacokinetic effects that albumin-binding introduces.

What is the molecular structure of CJC No DAC?

CJC No DAC has a molecular weight of 3367.9 Da and the molecular formula C₁₅₂H₂₅₂N₄₄O₄₂. It is built on the 29-amino-acid backbone corresponding to the N-terminal fragment of endogenous human GHRH — the same hGRF(1-29) region that defines other GHRH-class research peptides — modified with amino acid substitutions described in the literature as improving resistance to enzymatic cleavage. The sequence terminates in a C-terminal amide, a feature shared with native GHRH(1-29) and documented as relevant to receptor-binding activity.

The specific substitutions distinguishing CJC No DAC from unmodified GHRH(1-29) are designed to reduce susceptibility to the proteases that rapidly degrade the native hormone in solution and in cell-based systems, extending the practical window in which the compound remains intact during an in vitro experiment. The research-grade material is characterized to a purity specification of ≥99.3% by HPLC, and the lyophilized form is a white to off-white powder.

How does CJC No DAC relate to native GHRH and to CJC-1295 with DAC?

Endogenous human GHRH is a 44-amino-acid hypothalamic peptide that acts on pituitary somatotroph cells to stimulate growth hormone synthesis and release. The N-terminal 29 residues are established in early receptor-binding studies as sufficient for full GHRHR activation, which is why GHRH-class research peptides are built on that truncated fragment rather than the full-length hormone. CJC No DAC follows this same design logic, adding stabilizing substitutions on top of the 1-29 fragment.

The distinction from CJC-1295 with DAC is specifically the albumin-binding modification. CJC-1295 with DAC incorporates a linker chemistry that covalently or non-covalently associates the peptide with serum albumin, a modification studied for extending circulating exposure in vivo. CJC No DAC omits this modification entirely, so in an in vitro system — where there is no circulating albumin compartment to bind — its behavior is governed by the same receptor-binding and degradation kinetics that apply to other unmodified or lightly modified GHRH(1-29) analogs. This makes CJC No DAC the more direct in vitro comparator for isolating GHRHR pharmacology, while CJC-1295 with DAC is studied specifically for pharmacokinetic questions that require an albumin-binding component.

What receptor pharmacology is studied for CJC No DAC in pituitary cell culture models?

Published research characterizes GHRH-class peptides, including CJC No DAC, as agonists at the GHRH receptor (GHRHR), a class B G-protein-coupled receptor expressed on anterior pituitary somatotroph cells. In pituitary cell culture models, GHRHR activation is studied through its coupling to the Gs protein pathway: receptor engagement activates adenylyl cyclase, elevating intracellular cyclic AMP, which in turn activates protein kinase A (PKA) and downstream transcriptional machinery associated with GH gene expression and the somatotroph secretory pathway.

This Gs/cAMP/PKA cascade is the standard readout in pituitary cell culture experiments involving GHRH-class compounds, typically measured through cAMP accumulation assays or downstream reporter systems in immortalized or primary somatotroph cell lines. Because CJC No DAC shares the GHRHR-binding pharmacophore of native GHRH(1-29), it is used in these systems as a stabilized probe of the same signaling cascade, allowing longer assay windows without the rapid degradation that limits experiments using unmodified native hormone. Prove It Performance makes no therapeutic or outcome claims regarding CJC No DAC; it is studied solely for its receptor-pharmacology and signaling mechanisms in research settings.

What in vitro research models are used to study CJC No DAC?

Pituitary cell culture is the primary in vitro model system for CJC No DAC research, using either primary anterior pituitary cell preparations or immortalized somatotroph-lineage cell lines to characterize GHRHR binding, cAMP accumulation, and downstream GH gene transcription in response to compound exposure. These models are also used to study the regulatory interplay between GHRHR agonism and somatostatin, the primary inhibitory input on GH secretion, which acts through Gi-coupled receptors that suppress adenylyl cyclase activity — a competing signal that in vitro pituitary models are well suited to isolate and quantify independent of confounding systemic factors.

Comparative in vitro work also places CJC No DAC alongside ghrelin-receptor agonists such as ipamorelin, which act through the structurally distinct GHSR-1a receptor and a separate Gq/G11/calcium signaling cascade. Because the two receptor pathways are mechanistically independent, in vitro co-treatment studies in pituitary cell models are used to characterize the amplifying interaction between GHRHR-driven cAMP signaling and GHSR-1a-driven calcium signaling — a well-documented pharmacological interaction in the published GH secretagogue literature, and a common experimental design where CJC No DAC and ghrelin-receptor agonists appear in the same protocol.

How does CJC No DAC's in vitro profile compare to sermorelin in pituitary cell models?

Sermorelin acetate is another GHRH(1-29)-class research peptide that shares the same 29-residue backbone and GHRHR-agonist mechanism as CJC No DAC, which makes the two a useful comparison pair in pituitary cell culture research. Sermorelin is the acetate salt of the unmodified hGRF(1-29) sequence, while CJC No DAC carries additional stabilizing substitutions layered onto that same backbone. In a cell-based assay, this distinction shows up primarily as a difference in the practical stability of the compound in solution over the course of an experiment rather than as a difference in the receptor being engaged — both compounds are studied as GHRHR agonists acting through the same Gs/cAMP/PKA cascade in somatotroph cell models.

Because the two compounds converge on the same receptor and signaling pathway, in vitro studies that run them in parallel are typically designed to characterize assay-window and degradation-kinetics questions — how long a GHRHR-agonist signal can be sustained in a given cell culture system — rather than to compare distinct mechanisms. This makes CJC No DAC and sermorelin complementary reference compounds within the same GHRH-class research program: one representing the unmodified native fragment, the other representing a stabilized variant of it. For a detailed look at the unmodified comparator, see our sermorelin acetate research overview.

What is known about CJC No DAC's stability and handling in research?

CJC No DAC is supplied as a lyophilized powder and stored at −20°C to preserve structural integrity. As with other GHRH-class peptides, the compound is sensitive to oxidation, moisture, and repeated freeze-thaw cycling, all of which can compromise the peptide before it reaches an in vitro assay. Research handling practices that support reproducibility include maintaining cold storage, limiting freeze-thaw exposure, and protecting the lyophilized material from ambient humidity.

Cold-chain handling during shipping protects this same integrity in transit. A compound characterized at ≥99.3% purity at manufacture can degrade under thermal stress before it reaches the lab, which is one reason cold-chain packaging is standard for peptides of this class. For more on how temperature affects peptide integrity during shipping, see cold-chain shipping for research peptides. This article does not provide reconstitution or preparation instructions; all handling protocols are determined by the researcher according to their experimental requirements and applicable regulations.

How does Prove It Performance source CJC No DAC?

Prove It Performance supplies CJC No DAC as a research-grade compound held to a purity specification of ≥99.3% by HPLC, with mass spectrometry identity confirmation included in the batch-specific Certificate of Analysis shipped with every order. Cold-chain packaging is standard on all shipments, not an optional upgrade. Operations are US-based. For guidance on qualifying a research peptide supplier, see research peptide supplier qualification, and for interpreting batch COA documentation, see how to read a Certificate of Analysis.

Researchers can review specifications, available sizes, and pricing on the CJC No DAC product page, or browse the full catalog at all compounds. For a related ghrelin-receptor agonist studied alongside CJC No DAC in GH secretagogue research, see our ipamorelin research overview. All material is intended for laboratory research use only.

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This compound is a research chemical intended for laboratory and scientific research purposes only. It is not a drug, supplement, or food, and is not intended to diagnose, treat, cure, or prevent any disease. Prove It Performance does not sell products intended for human use. Researchers are responsible for compliance with all applicable local, state, and federal regulations.