CJC-1295 Without DAC: GHRH Analogue Research Overview
What is CJC-1295 without DAC?
CJC-1295 without DAC — also called Modified GRF(1-29) — is a lab-made peptide (a short chain of amino acids, the building blocks of proteins). In studies, it acts like GHRH, a natural hormone that tells the body to release its own growth hormone in short bursts. It is sold only as a research chemical for in vitro (lab) use, not for use in people or animals.
GHRH stands for growth-hormone-releasing hormone. Its first 29 amino acids hold almost all of its power to switch on its target, so scientists call that piece GHRH(1-29). CJC-1295 starts from that piece and swaps in four amino acids that protect it from enzymes — tiny molecular “scissors” in the blood (such as one called DPP-IV) that would normally chop up natural GHRH within minutes. The result is a peptide that lasts noticeably longer than plain GHRH(1-29) but still works in short bursts.
The words “without DAC” are the key point. DAC (short for Drug Affinity Complex) is an extra chemical handle that grabs onto albumin (a common blood protein) so the peptide stays active for days. The version without DAC leaves that handle off, so it works for only about half an hour instead of days. That short, bursty action is what makes it useful for studying how the GHRH target switches on. These are research observations only, not therapeutic effects.
GHRH-receptor activation and GH pulse research
CJC-1295 research follows the same plan as other GHRH-like peptides: switch on the target, see how long the effect lasts, and compare the DAC and no-DAC versions on purpose.
Receptor mechanism
Like Tesamorelin, CJC-1295 without DAC docks onto the GHRH receptor (the matching “lock” for this peptide) on somatotroph cells in the pituitary — a small gland at the base of the brain. Somatotroph cells are the ones that make growth hormone. Docking there raises a cell messenger called cAMP and gets those cells to make and release the body’s own growth hormone. It works one step before growth hormone rather than adding growth hormone directly, so the gland keeps its own natural controls in research models.
Half-life and pulse amplitude
The main research feature of the no-DAC form is that it acts for only a short time — about 30 minutes. (“Half-life” just means how long it takes for half of it to break down or clear.) That short window is studied for producing separate bursts of growth hormone that look a lot like the body’s natural rhythm. Studies report that this natural burst pattern is kept under CJC-1295, with higher growth hormone and higher IGF-1 (a protein the body makes in response to growth hormone), rather than the rhythm being flattened out. These are research observations only, not therapeutic effects.
DAC vs without-DAC: complementary research tools
The DAC form keeps the target switched on for days, while the no-DAC form gives one short burst. That makes them a useful pair in the lab: researchers can separate the pattern of switching on the target (steady vs bursty) from the simple fact that it is switched on, and then study how that pattern changes growth hormone and IGF-1 over time.
Key research findings
The following peer-reviewed studies are representative of the CJC-1295 / GHRH-analogue literature and are summarised for scientific reference only. Some examine the DAC-conjugated form; they are included for shared mechanistic context.
Characterised the GRF(1-29) analogue platform and confirmed activation of the pituitary GRF receptor, defining the molecule from which both the DAC and non-DAC forms derive.
PMID: 15817669
A preclinical study reporting that CJC-1295 restored normal growth in GHRH-deficient mice, demonstrating functional GHRH-receptor agonism in an animal model.
PMID: 16822960
Reported that GH pulsatility was preserved under CJC-1295 stimulation, with increased mean GH and IGF-1 — human data included for mechanistic context on how GHRH-receptor stimulation interacts with the natural GH rhythm.
PMID: 17018654
CJC-1295 and Tesamorelin
CJC-1295 without DAC and Tesamorelin are both GHRH-like peptides that switch on the same target, so they give researchers two related tools that differ in their amino-acid makeup and in how long they last. They are often studied together in the somatotropic research category (“somatotropic” just means “to do with growth hormone”). See the Tesamorelin research overview, or the CJC-1295 vs Tesamorelin side-by-side comparison.
Velox Peptides supply information
Velox Peptides supplies CJC-1295 without DAC as a lyophilised (freeze-dried) powder, tested to ≥99.1% purity by HPLC (a lab method that checks how pure a sample is). A batch certificate of analysis (a lab report on that batch) is available on request. To turn the powder back into a liquid, see the reconstitution calculator — reconstituting just means mixing the dried powder back into a liquid. Sold only as a research chemical for in vitro (lab) use.
References & further reading
- Jetté L et al. “hGRF(1-29)-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog.” Endocrinology, 2005. PMID: 15817669
- Alba M et al. “Once-daily administration of CJC-1295, a long-acting GHRH analog, normalizes growth in the GHRH knockout mouse.” 2006. PMID: 16822960
- Ionescu M, Frohman LA. “Pulsatile secretion of GH persists during continuous stimulation by CJC-1295.” 2006. PMID: 17018654
- Teichman SL et al. “Prolonged stimulation of growth hormone and IGF-I secretion by CJC-1295, a long-acting analog of GHRH.” Journal of Clinical Endocrinology & Metabolism, 2006. (Human clinical data — mechanistic context only.)
Summaries are paraphrased from the peer-reviewed literature. For full source citations, email veloxpeps@gmail.com.
