A practical reference on GRF(1-29): what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-03-15 and is reviewed periodically as new material appears.
Binding to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and stimulates growth hormone synthesis and release. Because the peptide acts upstream of the pituitary, effects are mediated through endogenous growth hormone rather than direct receptor activation in peripheral tissues. Increases in insulin-like growth factor 1 are generally described as a downstream consequence. Most published human exposure data come from small early-stage studies, and the clinical significance of the pharmacokinetic profile remains incompletely characterized.
CJC-1295 is a synthetic analogue of growth hormone-releasing hormone, built on the 29-amino-acid GHRH(1-29) fragment. Four substitutions distinguish it from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes reduce enzymatic cleavage and extend the peptide's persistence in circulation. The compound is discussed in two forms, one carrying a drug affinity complex and one without it.
Naming in this area is inconsistent, and readers should treat product labels with care. In much of the literature and in vendor catalogs, the unqualified term refers to the albumin-binding version, while the version lacking the DAC group appears as modified GRF(1-29), mod GRF(1-29), or the same name with a without-DAC qualifier. Because one abbreviation has been applied to both materials, the only reliable way to identify a sample is to check the stated sequence and the presence of the linker.
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.
| Property | Value | Notes |
|---|---|---|
| Physical form | Lyophilized white powder | Supplied as a freeze-dried solid for research use |
| Molecular weight | Approximately 3,647 Da (DAC form) | Lower for the variant lacking the albumin-binding moiety |
| Solubility | Soluble in water and aqueous buffer | Typically dissolved in sterile or bacteriostatic water |
| Typical storage temperature | −20 °C or below | Dry powder, desiccated and protected from light |
| Common analytical method | Reversed-phase HPLC with mass spectrometry | Used for purity estimation and identity confirmation |
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography combined with mass spectrometry. The chromatographic separation resolves the target peptide from truncation products and from species carrying oxidised residues, while mass measurement confirms the expected molecular mass. Because the two common variants differ by roughly 280 daltons, a mass determination distinguishes them unambiguously. Purity is often quoted as a percentage of total peak area, although that figure depends on the detection wavelength and the integration method applied.
Reported half-lives differ widely between the two variants and between species. Values for the albumin-binding form are usually expressed in days, while the unconjugated form is measured in minutes to a few hours. Sampling schedules, assay sensitivity, and route of administration all influence the numbers, which limits direct comparison across studies. Whether sustained receptor occupancy produces different downstream effects from pulsatile stimulation remains an open question in the published work. Claims about relative potency should therefore be read alongside the specific study design that produced them.
Lyophilised powder is the usual supplied form. The material is hygroscopic, so vials are typically equilibrated to room temperature before opening in order to prevent condensation on the contents. Long-term storage is generally described at minus twenty degrees Celsius or colder, protected from light and moisture. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of soluble material. A reconstituted solution is considerably less stable than the dry powder and is normally kept refrigerated for short periods only.
Two forms circulate in research settings and are frequently confused. One carries the drug affinity complex and is often written as CJC-1295 with DAC; the other lacks that group and is usually called modified GRF(1-29). The two share the same core sequence but differ sharply in how long they persist in blood. Products labelled only as CJC-1295 normally refer to the version carrying the complex. Documentation that omits the distinction leaves the intended molecule ambiguous.
CJC-1295 is a synthetic peptide built as a long-acting analogue of growth hormone-releasing hormone. Its backbone matches the first twenty-nine residues of the natural human hormone, with four amino acid substitutions added to slow enzymatic breakdown. A reactive maleimide group, commonly termed the drug affinity complex, allows the peptide to attach to circulating albumin after administration. That albumin attachment keeps the molecule in the bloodstream for an extended period instead of being cleared within minutes.
The peptide backbone includes a D-alanine at position two, which resists cleavage by dipeptidyl peptidase IV, and several other substitutions that reduce degradation. Its molecular weight is roughly 3.4 kDa without the linker and about 3.6 kDa with it. The molecule is water soluble and is normally supplied as a lyophilized powder. Precise sequence and mass values depend on which variant is described, so technical documents usually state the exact form being referenced.
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.
Laboratory handling centers on minimizing exposure to water, heat and oxygen before use. Working solutions are typically prepared in sterile water or a mild buffer, and any residual particulate matter is removed by filtration. When the powder dissolves slowly, a small proportion of acetonitrile or dilute acetic acid is sometimes added as a co-solvent. Containers are kept sealed and desiccated between uses. Records of lot number, reconstitution date and storage conditions support later comparison of results across experiments.
Identity and purity are established with reversed phase high performance liquid chromatography coupled to mass spectrometry. The chromatographic step separates the target peptide from truncated sequences and deletion products, while the mass measurement confirms the expected molecular weight to within a fraction of a dalton. Because the two common variants differ by the presence of the linker, mass alone can distinguish them in the unconjugated state. Amino acid analysis and peptide mapping are used when sequence level confirmation is required.
Lyophilized material is generally stable for extended periods when held at minus twenty degrees Celsius or below and protected from moisture and light. In solution the peptide is more labile; bond hydrolysis, aggregation and oxidation of susceptible residues all proceed faster at ambient temperature. Repeated freeze and thaw cycles should be avoided because they promote clumping and loss of soluble material. The conjugated variant adds a further consideration, since the maleimide group can hydrolyze in aqueous buffer and lose its ability to react with albumin.
Protection: One of the main functions of the oral mucosa is to physically protect the underlying tissues from the mechanical forces, microbes and toxins in the mouth. Keratinised masticatory mucosa is tightly bound to the hard palate and gingivae. It accounts for 25% of all oral mucosa. It supports underlying tissues by resisting the loading forces exerted during mastication. Lining mucosa in the cheeks, lips and floor of mouth is mobile to create space when chewing and talking. During mastication, it allows food to move freely around the mouth and physically protects the underlying tissues from trauma. It accounts for 60% of oral mucosa. Secretion: Saliva is the primary secretion of the oral mucosa. It has many functions including lubrication, pH buffering and immunity. The lubricating and antimicrobial functions of saliva are maintained mainly by resting; saliva results in a flushing effect and the clearance of oral debris and noxious agents. Saliva contains numerous antimicrobial proteins that help protect the oral ecosystem from infectious agent. The components like lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, and thiocyanate concentrations act as a defense mechanism in the saliva. Saliva is secreted from 3 pairs of major salivary glands (parotid, submandibular, sublingual) alongside many minor salivary glands. It also aids the initial chemical digestion of food as it contains the enzyme amylase, responsible for breaking carbohydrates into sugars.
The motor proteins actin and myosin generate the forces exerted by contracting muscles. Cortisol decreases amino acid uptake by muscle and inhibits protein synthesis. Current recommendations suggest that bodybuilders should consume 25–30% of protein per total calorie intake to further their goal of maintaining and improving their body composition. This is a widely debated topic, with many arguing that 1 gram of protein per pound of body weight per day is ideal, some suggesting that less is sufficient, while others recommending 1.5, 2, or more. It is believed that protein needs to be consumed frequently throughout the day, especially during/after a workout, and before sleep. There is also some debate concerning the best type of protein to take. Chicken, turkey, beef, pork, fish, eggs and dairy foods are high in protein, as are some nuts, seeds, beans, and lentils. Casein or whey are often used to supplement the diet with additional protein. Whey is the type of protein contained in many popular brands of protein supplements and is preferred by many bodybuilders because of its high biological value (BV) and quick absorption rates. Whey protein also has a bigger effect than casein on insulin levels, triggering about double the amount of insulin release. That effect is somewhat overcome by combining casein and whey.
Thus, the two substrates of this enzyme are prostaglandin D2 and oxidised nicotinamide adenine dinucleotide phosphate (NADP+). Its products are 15-dehydro-prostaglandin D2, reduced NADPH, and a proton. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (5Z,13E)-(15S)-9alpha,15-dihydroxy-11-oxoprosta-5,13-dienoate:NADP+ 15-oxidoreductase. Other names in common use include prostaglandin-D 15-dehydrogenase (NADP+), dehydrogenase, prostaglandin D2, NADP+-PGD2 dehydrogenase, dehydrogenase, 15-hydroxyprostaglandin (nicotinamide adenine, dinucleotide phosphate), 15-hydroxy PGD2 dehydrogenase, 15-hydroxyprostaglandin dehydrogenase (NADP+), NADP+-dependent 15-hydroxyprostaglandin dehydrogenase, prostaglandin D2 dehydrogenase, NADP+-linked 15-hydroxyprostaglandin dehydrogenase, NADP+-specific 15-hydroxyprostaglandin dehydrogenase, NADP+-linked prostaglandin D2 dehydrogenase, and 15-hydroxyprostaglandin-D dehydrogenase (NADP+). This enzyme participates in arachidonic acid metabolism.
=== Allergy diagnosis === Basophils are easily isolated from venous blood and present good "indicator cells" of an IgE-mediated allergic response based on the upregulation of activation markers such as CD63 and/or CD203c upon suspect allergen stimulation. Therefore, the BAT serves to confirm IgE-mediated allergy following uncertain results from classical testing based on anamnesis, skin testing or specific IgE results. More recently, BAT has also been used for the monitoring of successful allergen immunotherapy (desensitization) to differentiate short-term desensitization versus sustained unresponsiveness to the allergen.
==== Solution and precipitation ==== The diagram above illustrates the point that a precipitate that is not one of the main species in the solution equilibrium may be formed. At pH just below 5.5 the main species present in a 5 μM solution of Al3+ are aluminium hydroxides Al(OH)2+, AlOH+2 and Al13(OH)7+32, but on raising the pH Al(OH)3 precipitates from the solution. This occurs because Al(OH)3 has a very large lattice energy. As the pH rises more and more Al(OH)3 comes out of solution. This is an example of Le Châtelier's principle in action: Increasing the concentration of the hydroxide ion causes more aluminium hydroxide to precipitate, which removes hydroxide from the solution. When the hydroxide concentration becomes sufficiently high the soluble aluminate, Al(OH)−4, is formed. Another common instance where precipitation occurs is when a metal cation interacts with an anionic ligand to form an electrically neutral complex. If the complex is hydrophobic, it will precipitate out of water. This occurs with the nickel ion Ni2+ and dimethylglyoxime, (dmgH2): in this case the lattice energy of the solid is not particularly large, but it greatly exceeds the energy of solvation of the molecule Ni(dmgH)2.
Sources: en.wikipedia.org
At the time of the K-Pg extinction, the Deccan Traps flood basalts of India were actively erupting. The eruptions can be separated into three phases around the K-Pg boundary, two prior to the boundary and one after. The second phase, which occurred very close to the boundary, would have extruded 70 to 80% of the volume of these eruptions in intermittent pulses that occurred around 100,000 years apart. Greenhouse gases such as carbon dioxide and sulfur dioxide would have been released by this volcanic activity, resulting in climate change through temperature perturbations of roughly 3 °C (5.4 °F) but possibly as high as 7 °C (13 °F). Like the Chicxulub impact, the eruptions may also have released sulfate aerosols, which would have caused acid rain and global cooling. However, due to large error margins in the dating of the eruptions, the role of the Deccan Traps in the K-Pg extinction remains unclear. Before 2000, arguments that the Deccan Traps eruptions—as opposed to the Chicxulub impact—caused the extinction were usually linked to the view that the extinction was gradual. Prior to the discovery of the Chicxulub crater, the Deccan Traps were used to explain the global iridium layer; even after the crater's discovery, the impact was still thought to only have had a regional, not global, effect on the extinction event. In response, Luis Alvarez rejected volcanic activity as an explanation for the iridium layer and the extinction as a whole.
=== Data analysis === Mass spectrometry data analysis is specific to the type of experiment producing the data. General subdivisions of data are fundamental to understanding any data. Many mass spectrometers work in either negative ion mode or positive ion mode. It is very important to know whether the observed ions are negatively or positively charged. This is often important in determining the neutral mass but it also indicates something about the nature of the molecules. Different types of ion source result in different arrays of fragments produced from the original molecules. An electron ionization source produces many fragments and mostly single-charged (1-) radicals (odd number of electrons), whereas an electrospray source usually produces non-radical quasimolecular ions that are frequently multiply charged. Tandem mass spectrometry purposely produces fragment ions post-source and can drastically change the sort of data achieved by an experiment. Knowledge of the origin of a sample can provide insight into the component molecules of the sample and their fragmentations. A sample from a synthesis/manufacturing process will probably contain impurities chemically related to the target component. A crudely prepared biological sample will probably contain a certain amount of salt, which may form adducts with the analyte molecules in certain analyses. Results can also depend heavily on sample preparation and how it was run/introduced.
The Shihab dynasty was an Arab family whose members served as the paramount tax farmers and local chiefs of Mount Lebanon from the early 18th to mid-19th century, during Ottoman rule. Their reign began in 1697 after the death of the last Ma'nid chief. In 1697, Amir Ahmad died without an heir, and the Druze notables chose his nephew Bashir al-Shihabi as their new ruler. He was succeeded in 1707 by the young Amir Haydar al-Shihabi, grandson of Amir Ahmad al-Ma'ni. Haydar recognized the authority of the Maronite al-Khazins and the Hubayshis of Kisrawan and Ghazir and treated these two families as equal to the feudalistic Druze families. The Shihab family realized the importance of Maronite rule and power, and they and the Maronites became united in a common interest. The family centralized control over Mount Lebanon, destroying the feudal power of the mostly Druze lords and cultivating the Maronite clergy as an alternative power base of the emirate. During Yusuf Shihab's rule, many members of the Shihab family converted to Christianity and Yusuf also began to rely on the support of the Maronite Christians. On 3 September 1840, Bashir Shihab III, a distant cousin of the once-powerful Emir Bashir Shihab II, was appointed emir of Mount Lebanon by Ottoman Sultan Abdulmejid I. Geographically, the Mount Lebanon Emirate corresponded with the central part of present-day Lebanon, which historically has had a Christian and Druze majority. In practice, the terms "Lebanon" and "Mount Lebanon" tended to be used interchangeably by historians until the formal establishment of the Mandate.
=== Patients' rights to access unapproved drugs === The Compassionate Investigational New Drug program was created after Randall v. U.S. ruled in favor of Robert C. Randall in 1978, creating a program for medical marijuana. A 2006 court case, Abigail Alliance v. von Eschenbach, would have forced radical changes in FDA regulation of unapproved drugs. The Abigail Alliance argued that the FDA must license drugs for use by terminally ill patients with "desperate diagnoses", after they have completed Phase I testing. The case won an initial appeal in May 2006, but that decision was reversed by a March 2007 rehearing. The US Supreme Court declined to hear the case, and the final decision denied the existence of a right to unapproved medications. Critics of the FDA's regulatory power argue that the FDA takes too long to approve drugs that might ease pain and human suffering faster if brought to market sooner. The AIDS crisis created some political efforts to streamline the approval process. However, these limited reforms were targeted for AIDS drugs, not for the broader market. This has led to the call for more robust and enduring reforms that would allow patients, under the care of their doctors, access to drugs that have passed the first round of clinical trials.
Sources: en.wikipedia.org
The two share the same 29-amino-acid backbone. CJC-1295 carries an additional albumin-binding moiety that markedly extends its residence time in circulation, while the form without that moiety clears faster. Literature sometimes applies the name loosely to either variant.
It has not been approved by major regulatory agencies for any therapeutic indication. Material sold under this name is typically distributed for laboratory research only. Clinical use is not supported by large controlled trials.
Early human studies of the albumin-binding form reported circulation half-lives on the order of several days. The value depends on assay method and study design. Estimates for the form without the binding moiety are considerably shorter.
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.