If you have been reading about GRF(1-29) and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-05-02. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
CJC-1295 belongs to a family of synthetic peptides modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound is built from the first twenty-nine amino acids of the natural human sequence, a fragment that retains full receptor binding capacity. Native growth hormone-releasing hormone is degraded quickly in circulation, so the fragment alone has limited practical value. Early work therefore focused on chemical modifications that preserve receptor binding while slowing enzymatic breakdown. The result is a molecule described in the literature as a long-acting analog of the natural hormone.
| Property | Value | Notes |
|---|---|---|
| Purity assessment | Reverse-phase HPLC | Reported as area percentage |
| Identity confirmation | Mass spectrometry | Electrospray or laser desorption |
| Powder storage | Minus 20 degrees Celsius or lower | Dark and dry conditions |
| Solution storage | Two to eight degrees Celsius | Avoid repeated freeze-thaw |
| Appearance | White to off-white powder | Common lyophilized form |
CJC-1295 is the name used for a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound was described by a Canadian drug discovery company in the mid-2000s as a long-acting research tool. Two closely related molecules share the name in practice: one carries a drug affinity complex, or DAC, group, and one does not. The distinction matters because the two behave differently in circulation.
The peptide backbone corresponds to GRF(1-29), the first 29 residues of native growth hormone-releasing hormone, which retains most of the receptor-activating activity of the full-length molecule. Four substitutions distinguish the analog from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes slow cleavage by dipeptidyl peptidase IV, the enzyme that degrades native hormone in plasma within minutes. The outcome is improved enzymatic stability combined with a still brief residence time when no additional modification is present.
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.
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.
== Further reading == Verma, S; Bhargava, M; Mittal, SK; Gupta, R (1 January 2013). "Homozygous delta-beta Thalassemia in a Child: a Rare Cause of Elevated Fetal Hemoglobin". Iranian Journal of Pediatric Hematology and Oncology. 3 (1): 222–227. ISSN 2008-8892. PMC 3915439. PMID 24575268. Kumar, B. Vinodh; Choccalingam, Chidambharam; Samuel, Premila (1 March 2016). "Incidental Identification of Possible Delta-Beta Thalassemia Trait in a Family: A Rare Cause of Elevated Hb F." Journal of Clinical and Diagnostic Research. 10 (3): BD01–BD02. doi:10.7860/JCDR/2016/16352.7409. ISSN 2249-782X. PMC 4843246. PMID 27134860. "Public Health Information Network Vocabulary Access and Distribution System (PHIN VADS)". CDC. Centers for Disease Control. Retrieved 17 September 2016.
=== Recruitment and spending policy === Youth development and scouring for talent abroad is central to Wenger's recruitment policy. He relies on a network of scouts and personal contacts to find and attract talented footballers to play under him. Wenger's strategy is aided by data; for instance, the decision to sign Flamini in 2004 came about as he was looking at statistics to find an understudy to Vieira. To examine the mental state of a young footballer, he uses psychometric tests conducted by psychologist Jacques Crevoisier once every two years. Wenger prides himself on nurturing talent, saying in an interview: "I believe one of the best things about managing people is that we can influence lives in a positive way. That's basically what a manager is about. When I can do that, I am very happy". In his early managerial years, Wenger recognised the potential of football in Africa, which influenced his transfer dealings at Monaco. On the recommendation of Claude Le Roy, he signed Liberian George Weah, who later became the first African to be named FIFA World Player of the Year. Weah, while receiving his award from FIFA president João Havelange and vice-president Lennart Johansson invited Wenger up to the stage, spontaneously giving his medal to the manager, as a token of his appreciation. During his final years at Monaco, Wenger worked with Roger Mendy, a Senegalese defender regarded in 1991 as one of the ten best African footballers by France Football, and Nigerian Victor Ikpeba, a forward who earnt the accolade of African Player of the Year.
Education and health are provided mainly by member states, but shaped by common minimum standards in EU law. In the case of education, the European Social Charter, like the Universal Declaration, the International Bill of Human Rights, say that "everyone" has the right to education, and that primary, secondary and higher education should be made "free", for instance "by reducing or abolishing any fees or charges" and "granting financial assistance". While the history of education was confined to a wealth elite, today most member states have tuition free university. There are no common rules for university finance or governance, although there is a right to free movement and universities have voluntarily harmonised standards. In 1987, the Erasmus Programme was created to fund students to study in other countries, and with a budget of €30 billion from 2021 to 2027. From 1999, the Bologna Declaration and Process led to the creation of the European Higher Education Area where member state universities adopted a common degree structure (bachelor, master, and doctoral degree) with a goal to have similar expectations in learning outcomes. Member states may not impose different fees on students from other member states or limit their numbers, and this appears to have worked even without a system for countries to reimburse one another if costs differ widely. However, if member states have grants or student loans, R (Bidar) v London Borough of Ealing held there may be a minimum residency requirement, such as three years.
== Theca externa == The theca externa is the outer layer of the theca in the follicle. It is derived from connective tissue, the cells resemble fibroblasts, and contain abundant collagen. During ovulation, the surge in luteinizing hormone (LH surge) increases cAMP which increases progesterone and PGF2α production. PGF2α induces the contraction of the smooth muscle cells of the theca externa, increasing intrafollicular pressure. This aids in rupture of the mature oocyte, or immature oocyte at the germinal vesicle stage in the canine, along with plasmin and collagenase degradation of the follicle wall.
Sources: en.wikipedia.org
== Mechanism == The enzyme uses pyridoxal phosphate (PLP), the active form of vitamin B6, as a cofactor. PLP is essential to the mechanism of decarboxylation in AADC. In the active enzyme, PLP is bound to lysine-303 of AADC as a Schiff base. Upon substrate binding, Lys-303 is displaced by the substrate's amine. This positions the carboxylate of the substrate within the active site such that decarboxylation is favored. Decarboxylation of the substrate produces a quinonoid intermediate, which is subsequently protonated to produce a Schiff base adduct of PLP and the decarboxylated product. Lys-303 can then regenerate the original Schiff base, releasing the product while retaining PLP. Probing this PLP-catalyzed decarboxylation, it has been discovered that there is a difference in concentration and pH dependence between substrates. DOPA is optimally decarboxylated at pH 6.7 and a PLP concentration of 0.125 mM, while the conditions for optimal 5-HTP decarboxylation were found to be pH 8.3 and 0.3 mM PLP.
In Japan, the installation of a rotary engine gave Japanese buyers a financial advantage when it came time to pay the annual road tax in that they bought a car that was more powerful than a traditional inline engine, but without having the penalty for having an engine in the higher 1.0-litre tax bracket. This was the only generation of the Familia that had the rotary engine offered. When Mazda updated the rotary engine to single distributor design in late 1973 with a raft of improvements to improve reliability and fuel economy, the smaller 10A engine was discontinued. Upgrading the Familia Rotary to the 12A engine would have cost the car its tax advantage in Japan, and the decision to discontinue it was made, despite the Familia body continuing production for some years to follow. The R100 was one of the first Mazda cars imported into the United States for the new Mazda Motors of America, sold in model years 1971 and 1972. Due to US regulations it was released in North America with round headlights fitted in place of the rectangular lights fitted in all other markets. It was a surprising hit with the American public, though sales were limited to some Northwestern states initially. Following on the success of the Cosmo Sports at Nürburgring in 1968, Mazda decided to race another rotary car. The Familia Rotary coupé won its first outing, at the Grand Prix of Singapore, in April 1969. Next, the company took on the touring car endurance challenge at Spa, the Spa 24 Hours. For 1969, Mazda entered a pair of Familia Rotary coupés.
Besides these methods, other techniques such as SELEX, PBM (protein binding microarrays), DNA microarray screens, DamID, FAIRE or more recently DAP-seq (DNA affinity purification sequencing) are used in the laboratory to investigate DNA-protein interaction in vivo and in vitro.
Sources: en.wikipedia.org
The powder is normally held at minus twenty degrees Celsius or below. Light and moisture exposure should be minimized. Repeated warming and cooling cycles are avoided.
Reverse-phase high-performance liquid chromatography is used for purity. Mass spectrometry confirms molecular weight and sequence integrity. Amino acid analysis offers an additional compositional check.
Published stability data for dissolved material are limited and vary with conditions. Refrigerated solutions are generally used within a short period. The exact shelf life depends on concentration, buffer, and handling.
No. It is a laboratory-made analog of growth hormone-releasing hormone. The natural hormone is a 44-residue peptide, while the analog is built on a shorter 29-residue fragment.