en · de · es · fr · pt
faq-desk.peptides7250.com › Faq › Structure And Receptor Pharmacology — What the Evidence Shows

Structure And Receptor Pharmacology — What the Evidence Shows

By Editorial Desk · published 2026-03-12 · last reviewed 2026-05-04 · Faq

If you have been reading about CJC-1295 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.

Updated 2026-05-04. Numbers and descriptions here follow the published literature rather than marketing material.

Structure And Receptor Pharmacology

Two related forms appear under the CJC-1295 name. The simpler analogue, commonly written as modified GRF(1-29), carries the four substitutions but no additional conjugation. The second form attaches a maleimidopropionic acid linker to a lysine residue, a modification frequently called the drug affinity complex. That linker reacts with the free thiol on serum albumin to form a covalent bond. Because albumin has a long residence time in blood, the conjugated peptide stays in circulation far longer than the unconjugated analogue.

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.

Background and Molecular Features

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.

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 at a glance

PropertyValueNotes
Peptide classSynthetic GHRH analogueBuilt on a 29 residue sequence
Primary targetGHRH receptor (GHRHR)Class B G protein coupled receptor
Unconjugated half lifeMinutesLimited by protease degradation
Key modificationFour residue substitutionsPositions 2, 8, 15 and 27
Common synonymModified GRF(1-29)Usually denotes the form without DAC

Background and Receptor Mechanism

CJC-1295 is a synthetic peptide belonging to the growth hormone-releasing hormone analog family. It comprises twenty-nine amino acid residues derived from the N-terminal region of natural GHRH. The molecule incorporates several non-natural substitutions that increase resistance to enzymatic degradation. These modifications extend its activity compared with the native hormone fragment. Researchers use it to study pituitary growth hormone secretion in laboratory and clinical settings. This compound is distinct from native GHRH in its stability profile.

Two principal forms appear in the literature and in research supply. One carries a drug affinity complex, a maleimide-based group that forms a covalent bond with circulating albumin. This linkage slows clearance and produces a long-lasting elevation of peptide levels. The other form lacks that group and is often labeled MOD GRF(1-29). It has a much shorter circulation time. Both variants retain the same core receptor-binding sequence. Reported half-lives differ substantially between the two.

At the pituitary, the peptide binds the growth hormone-releasing hormone receptor on somatotroph cells. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone. Somatostatin and other hypothalamic signals modulate this response. Negative feedback from insulin-like growth factor 1 also influences output. The same regulatory architecture operates with the native hormone. Whether the synthetic analog alters feedback dynamics over repeated exposure remains an open question. Most published receptor work uses cell models rather than intact human systems.

Related pages on this site

Identity and Naming History

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.

Molecular Background and Naming

CJC-1295 is a synthetic peptide designed as a long-acting analogue of growth hormone-releasing hormone (GHRH). Its structure derives from the first 29 amino acids of native GHRH, a fragment often called GRF(1-29). Four substitutions were introduced to slow enzymatic breakdown and extend activity relative to the natural sequence. The compound was developed by ConjuChem as part of a broader effort to improve the pharmacokinetic profile of peptide hormones. It is studied in laboratory and clinical research settings rather than appearing as a naturally occurring substance.

Two related forms circulate in technical discussion under the same family name. The original version carries a drug affinity complex (DAC) that binds covalently to serum albumin after administration, and this linkage substantially extends circulation time. A second form, frequently written as modified GRF(1-29) or CJC-1295 without DAC, lacks that linker and clears much faster. The naming is a frequent source of confusion because the shorthand CJC-1295 can refer to either form depending on the source. Reports sometimes fail to specify which variant was studied.

Further detail

==== G protein-linked receptors ==== The G protein-linked signaling cascade can significantly amplify the signal of a particular neurotransmitter to produce hundreds to thousands of second messengers in a cell. The mechanism of action by which G protein-linked receptors cause a signaling cascade is as follows:

=== Other types === Other types of chocolate are used in baking and confectionery. These include baking chocolate (often unsweetened), couverture chocolate (used for coating), compound chocolate (a lower-cost alternative) and modeling chocolate. Modeling chocolate is a chocolate paste made by melting chocolate and combining it with corn syrup, glucose syrup, or golden syrup.

=== Under British Raj (1858–1947) === During the 1861-65 American Civil War, American Union blockades of Southern cotton led to the Indian press speculating about the opportunity for India to export more of its cotton. The impact on the British economy also drove the construction of the Indian Railways forward, as faster transport assisted in exporting Indian cotton. In the United States, as Northerners fretted about the ultimate status of African American slaves, The New York Times argued in the weeks leading up to President Abraham Lincoln's Emancipation Proclamation that African Americans could never rise in American society above the "condition which the inferior castes of India have always occupied." India's inability to defend itself from British conquests was also referenced; Lincoln and his Secretary of State William H. Seward agreed on the need to maintain American unity in part to avoid a similar fate as that of British India, and throughout the previous decade, Southerners who sought to expand the institution of slavery to new territories referred to the rapid white conquest of places like India to justify colonizing nonwhite territories south of the United States (see also: Knights of the Golden Circle). The 1869 opening of the Suez Canal was celebrated by famous American poet Walt Whitman, who saw it as a way to connect West and East and tie into the last stage of global consolidation through American expansion.

Sources: en.wikipedia.org

Supporting material

=== Amino acid enrichment for certain functional categories of LCRs === A bioinformatics analysis of prokaryotic LCRs identified 5 types of amino acid enrichment, for certain functional categories of LCRs:

In the spring of 1945, tensions between communists and farmers in the Fatherland Front intensified and led to the split of the BZNS. The main part of the organization, headed by Nikola Petkov (BZNS - Nikola Petkov), went into opposition and was replaced in the government by representatives of the pro-communist wing (BZNS (Kazionen). In this environment, in June, Kimon Georgiev and Damyan Velchev met with Traicho Kostov and received assurances about the preservation of the Fatherland Front as a multi-party coalition, as well as for its own positions in the government. As a result, during the 1945 crisis, Zveno remained in the Fatherland Front, with Georgiev remaining fully loyal to the Communists and playing an important role in neutralizing opposition sentiment within Zveno itself. Georgiev's government scheduled elections for 26 August 1945, despite the protests of the opposition, which had no right to exist legally. Bulgaria was under intense pressure from the United States and Britain to postpone the elections to allow them to be held freely, but the Communists firmly refused. Only a day before the date of the elections they were postponed until November on Stalin's personal instructions. In the following weeks the opposition parties were legalised and martial law was lifted. At the elections held on 18 November, which were boycotted by the opposition, Kimon Georgiev was elected as a deputy in Burgas. In December, the United States and Britain made the inclusion of two opposition representatives in the Bulgarian government a condition for its recognition.

== Biological roles == Human uses of AGPs include the use of gum arabic in the food and pharmaceutical industries because of natural properties in thickening and emulsification. AGPs in cereal grains have potential applications in biofortification, as sources of dietary fibre to support gut bacteria and protective agents against ethanol toxicity. AGPs are found in a wide range of plant tissues, in secretions of cell culture medium of root, leaf, endosperm and embryo tissues, and some exudate producing cell types such as stylar canal cells. AGPs have been shown to regulate many aspects of plant growth and development including male-female recognition in reproduction organs, cell division and differentiation in embryo and post-embryo development, seed mucilage cell wall development, root salt tolerance and root-microbe interactions. These studies suggest that they are multifunctional, similar to what is found in mammalian proteoglycans/glycoproteins. Conventional methods to study functions of AGPs include the use of β-glycosyl (usually glucosyl) Yariv reagents and monoclonal antibodies (mAbs). β-Glycosyl Yariv reagents are synthetic phenylazo glycoside probes that specifically, but not covalently, bind to AGPs and can be used to precipitate AGPs from solution. They are also used commonly as histochemical stains to probe the locations and distribution of AGPs. A number of studies have shown that addition of β-Yariv reagents to plant growth medium can inhibit seedling growth, cell elongation, block somatic embryogenesis and fresh cell wall mass accumulation.

Sources: en.wikipedia.org

Supporting material

While some forms of aquaculture can be devastating to ecosystems, such as shrimp farming in mangroves, other forms can be beneficial. Shellfish aquaculture adds substantial filter feeding capacity to an environment which can significantly improve water quality. A single oyster can filter 15 gallons of water a day, removing microscopic algal cells. By removing these cells, shellfish are removing nitrogen and other nutrients from the system and either retaining it or releasing it as waste which sinks to the bottom. By harvesting these shellfish, the nitrogen they retained is completely removed from the system. Raising and harvesting kelp and other macroalgae directly remove nutrients such as nitrogen and phosphorus. Repackaging these nutrients can relieve eutrophic, or nutrient-rich, conditions known for their low dissolved oxygen which can decimate species diversity and abundance of marine life. Removing algal cells from the water also increases light penetration, allowing plants such as eelgrass to reestablish themselves and further increase oxygen levels. Aquaculture in an area can provide for crucial ecological functions for the inhabitants. Shellfish beds or cages can provide habitat structure. This structure can be used as shelter by invertebrates, small fish or crustaceans to potentially increase their abundance and maintain biodiversity. Increased shelter raises stocks of prey fish and small crustaceans by increasing recruitment opportunities in turn providing more prey for higher trophic levels.

Historians have explored how the Napoleonic wars became total wars. Most historians argue that the escalation in size and scope came from two sources. First was the ideological clash between revolutionary/egalitarian and conservative/hierarchical belief systems. Second was the emergence of nationalism in France, Germany, Spain, and elsewhere, that made these "people's wars" instead of contests between monarchs. Bell has argued that even more important than ideology and nationalism were the intellectual transformations in the culture of war that came about through the Age of Enlightenment. One factor, he says, is that war was no longer a routine event but a transforming experience for societies—a total experience. Secondly, the military emerged in its own right as a separate sphere of society distinct from the ordinary civilian world. The French Revolution made every civilian a part of the war machine, either as a soldier through universal conscription, or as a vital cog in the home front machinery supporting and supplying the army. Out of that, says Bell, came "militarism", the belief that the military role was morally superior to the civilian role in times of great national crisis. The fighting army represented the essence of the nation's soul. As Napoleon proclaimed, "It is the soldier who founds a Republic and it is the soldier who maintains it." Napoleon said on his career "I closed the gulf of anarchy and brought order out of chaos. I rewarded merit regardless of birth or wealth, wherever I found it.

== Clinical significance == It has been shown that low levels of glutathione peroxidase as measured in the serum may be a contributing factor to vitiligo. Lower plasma glutathione peroxide levels were also observed in patients with type 2 diabetes with macroalbuminuria and this was correlated to the stage of diabetic nephropathy. In one study, the activity of glutathione peroxidase along with other antioxidant enzymes such as superoxide dismutase and catalase was not associated with coronary heart disease risk in women. Glutathione peroxidase activity was found to be much lower in patients with relapsing-remitting multiple sclerosis. One study has suggested that glutathione peroxidase and superoxide dismutase polymorphisms play a role in the development of celiac disease. The activity of this enzyme has been reported to be decreased in case of copper deficiency in the liver and plasma.

Sources: en.wikipedia.org

Frequently asked questions

Is CJC-1295 the same as modified GRF(1-29)?

The names are often used interchangeably in casual writing, but they are not strictly identical. Modified GRF(1-29) refers to the unconjugated analogue carrying only the four substitutions. The version sold as CJC-1295 with DAC includes the albumin binding linker and clears much more slowly.

What does the acronym DAC refer to?

DAC stands for drug affinity complex, a term describing the maleimidopropionic acid linker. This group forms a covalent bond with the cysteine residue on serum albumin after administration. The resulting adduct is what extends the circulating half life from minutes to days.

Does this peptide occur naturally in the body?

No. It is entirely synthetic and does not correspond to any known endogenous peptide. The design starts from human growth hormone releasing hormone and introduces deliberate substitutions. Any biological effect comes from mimicking the natural hormone at its receptor.

What is the difference between CJC-1295 and natural GHRH?

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.

Network