CJC-1295 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-02-25. Numbers and descriptions here follow the published literature rather than marketing material.
Downstream of growth hormone, the liver and other tissues increase production of insulin-like growth factor 1, a mediator of many growth-promoting effects. Studies have documented elevated levels of both hormones after dosing, and the rise from the long-acting form persists longer than that produced by shorter-acting analogues. What remains unclear is whether sustained elevation of these markers translates into meaningful clinical benefit, and whether prolonged exposure carries risks that short trials could not detect.
CJC-1295 acts at the growth hormone-releasing hormone receptor, a G-protein-coupled receptor found on somatotroph cells in the anterior pituitary. Binding triggers a rise in cyclic AMP and calcium entry, which promotes release of stored growth hormone. Because the peptide mimics the body's own releasing hormone, it amplifies existing secretory pulses rather than driving continuous output. The size of the response therefore depends partly on the subject's own hormonal rhythm and feedback state.
The attached maleimide group explains the unusual duration of the DAC version. After injection it reacts with the thiol of cysteine-34 on serum albumin, forming a stable covalent bond. The resulting conjugate is too large for rapid kidney filtration and is shielded from many peptidases. Reported half-lives for this form reach several days, whereas the version without the group is cleared in roughly half an hour. That gap is the main pharmacological difference between the two.
The core sequence keeps the receptor-binding region of GHRH while replacing four positions that are vulnerable to dipeptidyl peptidase-4 and other proteases. Substitutions at positions 2, 8, 15, and 27 raise metabolic stability relative to the natural hormone. The N-terminal residues remain essential for activity, so changes there generally lower potency. Molecular weight sits near 3368 daltons for the tetrasubstituted analog without the linker, while the albumin-binding form is heavier because of the added maleimide group.
CJC-1295 is a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. Its sequence corresponds to the first twenty-nine residues of human GHRH, with four substitutions that slow enzymatic breakdown. Early descriptions placed the compound in research on growth hormone deficiency and related conditions, and later literature groups it with the long-acting GHRH analogs. The name appears in both laboratory and popular fitness writing, where it sometimes labels chemically different peptides.
Two related peptides circulate under the CJC-1295 label, and they differ mainly in how long they persist in circulation. The version carrying a drug affinity complex includes a maleimidopropionic acid linker that forms a covalent bond with serum albumin. The other version, usually written as modified GRF(1-29) or tetrasubstituted GRF(1-29), lacks that linker and is cleared quickly. Mixing the two produces inconsistent readings of published half-life values, because the linker rather than the receptor-facing sequence drives most of the difference.
| Property | Value | Notes |
|---|---|---|
| Primary target | GHRH receptor | G-protein-coupled receptor on pituitary somatotrophs |
| Half-life, long-acting form | Several days | Extended by covalent albumin binding |
| Half-life, short form | About 30 minutes | Cleared rapidly by peptidases and kidneys |
| Route in studies | Subcutaneous injection | Used in the published human trials |
| Main measured effect | Rise in GH and IGF-1 | Surrogate markers rather than clinical endpoints |
Enzymatic protection is a separate mechanism from plasma protein binding. The four substitutions in the backbone reduce recognition by dipeptidyl peptidase IV, which normally cleaves the natural hormone within minutes. Without the reactive group, this resistance still yields only a short window of activity, generally reported in the range of tens of minutes. With it, reported half-lives in early human work extended to several days. The size of that gap is the main practical distinction between the two materials.
Both forms act at the pituitary receptor for growth hormone-releasing hormone and increase growth hormone output, which in turn raises insulin-like growth factor 1. A long-acting analog produces sustained rather than pulsatile stimulation, and the physiological consequences of that pattern are not fully settled. Published human data on the extended form remain limited, and much of what circulates in discussion traces to early company reports rather than independent replication. How sustained exposure affects normal feedback remains an open question.
The distinguishing feature of the DAC form is a maleimide-containing group that reacts with the free thiol of cysteine-34 on human serum albumin. This reaction forms a covalent bond without enzymatic assistance, and it takes place after the peptide enters the bloodstream. Because albumin is abundant and long-lived, the attached peptide is carried through circulation far longer than an unmodified fragment would survive. The chemistry is a deliberate pharmacokinetic strategy rather than a change to receptor activity.
Reconstitution is typically performed with sterile water or bacteriostatic water, added slowly against the vial wall. The resulting solution should be clear and colorless; cloudiness or visible particles suggest a problem with the material or the diluent. Once in solution, the peptide is less stable than the dry powder. Refrigerated storage at two to eight degrees Celsius is common for short-term holding, while freezing aliquots is described for longer periods.
Purity is most often assessed by reversed-phase high-performance liquid chromatography, reported as a percentage of total peak area. Identity is confirmed by mass spectrometry, which yields a molecular ion consistent with the expected sequence. Amino acid analysis and peptide mapping provide additional characterization. Reported purity values are method-dependent, so figures from different laboratories are not always directly comparable without details of column, gradient, and detection wavelength.
Receptor level activity follows the canonical GHRH pathway. The peptide binds the GHRH receptor, a class B G protein coupled receptor on somatotroph cells of the anterior pituitary. Binding raises intracellular cyclic AMP, which promotes calcium entry and the release of growth hormone into the bloodstream. Because the molecule acts at the same receptor as the endogenous hormone, its effect is superimposed on the natural pulsatile rhythm rather than replacing it. Whether sustained receptor occupation leads to desensitization is not fully settled.
CJC-1295 belongs to a class of synthetic peptides modeled on growth hormone releasing hormone, a forty-four amino acid signal produced by the hypothalamus. The compound is built from the first twenty-nine residues of the natural sequence, with four substitutions introduced at positions 2, 8, 15 and 27. These changes were designed to slow enzymatic breakdown while preserving receptor activation. The result is a peptide that is shorter than native GHRH and considerably more resistant to ordinary clearance pathways in circulation.
Reverse-phase high-performance liquid chromatography is the standard tool for purity assessment. The technique separates the target peptide from truncated or modified byproducts. Mass spectrometry confirms molecular weight and supports sequence verification. Electrospray ionization and matrix-assisted laser desorption are both used. Amino acid analysis provides an independent check on composition. Purity values are commonly reported as area percentage from the chromatogram. Residual trifluoroacetate and water content are also measured in many quality programs.
Batch-to-batch consistency depends on solid-phase peptide synthesis and subsequent purification. Coupling efficiency, resin choice, and cleavage conditions all affect the final profile. Counter-ion content and moisture can shift the apparent mass of a batch. Documentation typically includes a certificate of analysis with chromatograms and spectra. Independent verification by a second laboratory is sometimes requested. Whether a given certificate reflects the actual vial contents depends on chain of custody. Analytical methods themselves carry uncertainty that should be stated alongside results.
Lyophilized material is typically stored at minus twenty degrees Celsius or lower. Keeping the vial dry and protected from light preserves peptide integrity. Repeated freeze-thaw cycles can cause aggregation or loss of activity. Once dissolved, solutions are generally kept at two to eight degrees Celsius. Stability data for reconstituted solutions vary, and long-term behavior is not fully established. Working aliquots reduce the number of times a stock container is opened.
== Biological function == Oxytocin has peripheral (hormonal) actions and also acts in the brain. Its actions are mediated by specific oxytocin receptors. The oxytocin receptor is a G protein-coupled receptor (GPCR), OT-R, which requires magnesium and cholesterol and is expressed in myometrial cells. It belongs to the rhodopsin-type (class I) group of G protein-coupled receptors. Studies have looked at oxytocin's role in various behaviors, including orgasm, social recognition, pair bonding, anxiety, in-group bias, situational lack of honesty, autism, and maternal behaviors. Oxytocin is believed to have a significant role in social learning. There are indicators that oxytocin may help reduce noise in the brain's auditory system, increase perception of social cues, and support more targeted social behavior. It may also enhance reward responses. However, its effects may be influenced by context, such as the presence of familiar or unfamiliar individuals. In addition to its oxytocin receptor agonism, oxytocin has been found to act as a PAM of the μ- and κ-opioid receptors and this may be involved in its analgesic effects.
=== Insulin delivery === Aquasomes with calcium phosphate ceramic cores may be useful for the pharmaceutical administration of substrates such as insulin where drug action is conformationally specific. In a 2000 study by Cherian et al., disaccharides such as trehalose were used to coat the core before insulin was loaded onto the coated cores via adsorption. Albino rats were used as test subjects to test these aquasome insulin formulations, and the efficiency of different carbohydrate coat molecules on the aquasome was explored. Pyridoxal-5-phosphate-coated particles were shown to lower blood glucose levels more efficiently when compared to trehalose- or cellobiose-coated particles, which may be due to their differences in structural stability. The use of these nanoparticles for the delivery of insulin in vivo in rabbits demonstrated that insulin-bearing aquasomes showed slower release and prolonged activity compared to standard insulin solution. Similar to their role in carrying hemoglobin, the carbohydrate layer of aquasomes may be responsible for the ability to protect insulin from degradation when injected subcutaneously as in the albino rats tested. Aquasomes were also shown to release insulin in controlled manners, mimicking the typical release of insulin from the pancreas.
they do not experience a resultant force; they pass freely through a slit, and are then subject to another magnetic field, transversing a semi-circular path and striking a photographic plate. The mass of the isotope is determined through subsequent calculation.
are not two constants but some random variables (a pair for each individual). This procedure has several names : "heterogeneous model", "structuration" (see also below for age structured models) or "Bayesian" view. Surprising results emerge, for instance it was proved in that the number of infected at the peak of a heterogeneous epidemic is smaller than the deterministic epidemic having same average
19 September — Commuters are stranded for three hours on a Metlink Waikanae train after an overhead power cable was detached at 7:40 am. 20 September – Thousands gather in various centres across New Zealand including Christchurch to oppose the Government's pay equity changes. 22 September – A partial solar eclipse occurs above mainland New Zealand, starting at sunrise and reaching maximum around 7 am. Views from most of the North Island are blocked by clouds. 23 September – Hakyung Lee is convicted by the Auckland High Court of murdering her two children in 2022. 24 September – Anna Breman is designated as the first female Governor of the Reserve Bank of New Zealand. 25 September — The New Zealand Government reopens applications for oil and gas exploration throughout the country. 26 September The Sealord Group proposes reducing its Nelson wetfish and by-products factories and fresh fish trawler operations from full-time to seasonal operations; potentially affecting 59 roles. Esarona David Lologa is convicted by a jury of the High Court in Wellington of carrying out the Loafers Lodge fire in 2023. Foreign Minister Winston Peters confirms during the 80th session of the United Nations General Assembly that New Zealand will not recognise Palestinian statehood. 27 September – The Presbyterian Church of Aotearoa New Zealand issues its first apology to survivors of historical abuse in care in Dunedin. 28 September — Four measles cases (three historical and one linked to international travel) are reported in the Northland Region.
Sources: en.wikipedia.org
=== Capping agents === A capping agent is used during nanoparticle synthesis to inhibit particle growth and aggregation. The chemical blocks or reduces reactivity at the periphery of the particle—a good capping agent has a high affinity for the new nuclei. Citrate ions or tannic acid function both as a reducing agent and a capping agent. Less sodium citrate results in larger particles.
== Types == Alkaptonuria Aspartylglucosaminuria Branched-chain keto acid dehydrogenase kinase deficiency Methylmalonic acidemia Maple syrup urine disease Homocystinuria Tyrosinemia Trimethylaminuria Hartnup disease Biotinidase deficiency Ornithine carbamoyltransferase deficiency Carbamoyl-phosphate synthase I deficiency disease Citrullinemia Hyperargininemia Hyperhomocysteinemia Hypermethioninemia Hyperlysinemias Nonketotic hyperglycinemia Propionic acidemia Hyperprolinemia
About 75% can be found in the dorsal area. Most of the congenital type-III cysts can be found posteriorly to the spinal cord, as opposed to those caused by trauma which can be found anteriorly to the spinal cord.Post traumatic inflammation induces cavitation and cystic formation and leads to greater secondary CNS injury. Cellular migration causing these cyst cavities was observed both in vitro and in vivo and cavitation was observed to be prevented with the use of an anti-inflammatory. Further more migration inflammatory cells into traumatized tissue has been observed with inflammation.
=== Off-label drugs === α2-Adrenergic receptor agonists (e.g., clonidine, tizanidine) Acetaminophen (paracetamol) Adenosine receptor antagonists (e.g., caffeine) Angiotensin-converting-enzyme inhibitors (ACE inhibitors) (e.g., lisinopril) Angiotensin receptor antagonists (e.g., candesartan, telmisartan) Antipsychotics and related (e.g., prochlorperazine, metoclopramide, haloperidol, promethazine, chlorpromazine) Anticonvulsants (e.g., valproic acid) Barbiturates (e.g., butalbital, proxibarbital) Beta blockers (β-adrenergic receptor antagonists) (e.g., propranolol, metoprolol, nadolol, timolol, atenolol) Calcium channel blockers (e.g., verapamil, nimodipine, nifedipine, diltiazem) Cannabinoids (cannabinoid receptor agonists) (e.g., cannabis, tetrahydrocannabinol (THC)) Corticosteroids (e.g., dexamethasone, prednisone) Ergoline monoamine receptor modulators (e.g., ergotamine, methylergometrine, methysergide, dihydroergocryptine, bromocriptine, lisuride) Estrogens (estrogen receptor agonists) (e.g., estradiol, ethinylestradiol) Gabapentinoids (α2δ subunit-containing volate-gated calcium channel ligands) (e.g., gabapentin, pregabalin) Melatonin Nonsteroidal anti-inflammatory drugs (NSAIDs; COX inhibitors) (e.g., ibuprofen, aspirin, naproxen, diclofenac, ketorolac, ketoprofen) Opioids (μ-opioid receptor agonists) (e.g., morphine, codeine, oxycodone, hydrocodone) Progestogens (progesterone receptor agonists) (e.g., progesterone, medroxyprogesterone acetate) Propofol Serotonergic psychedelics (e.g., psilocybin, lysergic acid diethylamide (LSD), dimethyltryptamine (DMT)) Serotonin receptor antagonists (e.g., methysergide, pizotifen, cyproheptadine) Sodium channel blockers (e.g., lidocaine) Tetracyclic antidepressants (TeCAs) (e.g., mianserin, mirtazapine) Tricyclic antidepressants (TCAs) (e.g., amitriptyline, nortriptyline, imipramine)
Sources: en.wikipedia.org
It binds the growth hormone-releasing hormone receptor on pituitary somatotroph cells. Receptor activation raises cyclic AMP and promotes release of stored growth hormone granules. Because the peptide persists longer than natural releasing hormone, stimulation is prolonged rather than brief.
The drug affinity complex links the peptide to serum albumin through a covalent bond. The conjugate is too large to be filtered quickly by the kidneys and is shielded from enzymatic breakdown. This extends the apparent half-life from roughly minutes to several days.
Long-term safety and any clinical benefit are unestablished. Published human data cover small groups over limited periods and focus on hormone levels rather than health outcomes. Whether prolonged elevation of growth hormone and insulin-like growth factor 1 is beneficial or harmful is an open question.
Natural GHRH is degraded quickly by dipeptidyl peptidase-4 and related enzymes, giving it a half-life measured in minutes. CJC-1295 carries substitutions that slow that breakdown, so it stays intact longer. Both act at the same pituitary receptor and produce the same class of signal.