A practical reference on GHRH analog: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-10-19. Anything still debated is marked as such rather than presented as settled.
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.
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.
Lyophilized peptide powder is comparatively stable when kept dry, cold, and protected from light. Once dissolved, the molecule is vulnerable to deamidation, oxidation, and aggregation, with the rate depending on pH, buffer composition, and temperature. Alkaline conditions and repeated freeze-thaw cycles accelerate loss of the intact peptide. The methionine present in the native sequence is a known oxidation site, which is one reason it was replaced in the modified fragment. Suppliers typically recommend cold storage of solutions and use within a short window.
Analytical confirmation usually relies on reversed-phase high-performance liquid chromatography for purity and on liquid chromatography coupled to mass spectrometry for identity. Mass data reveal the expected molecular mass and can flag truncated or oxidized species. Amino acid analysis and peptide mapping provide sequence-level verification. Immunoassays are used in some biological matrices, but antibodies raised against one releasing-hormone analog may cross-react with another. Reported purity figures depend heavily on the method used, so comparisons between suppliers require matching the analytical approach.
The two variants differ dramatically in how long they persist in circulation. The form lacking the albumin-binding group has a plasma half-life measured in tens of minutes, comparable to the natural hormone fragment. The version carrying the drug affinity complex binds albumin and shows a half-life of roughly six to eight days in human studies. That figure comes from small trials that tracked hormone levels over extended periods. The physiological consequences of sustained versus pulsatile stimulation are still debated and the literature does not settle the point.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | GHRH analog, not a steroid |
| Backbone length | 29 amino acids | Based on GRF(1-29) |
| Substitutions | Four positions | D-Ala2, Gln8, Ala15, Leu27 |
| Appearance | White to off-white powder | Typical lyophilized research material |
| Common synonyms | Modified GRF(1-29) | Usage varies between sources |
CJC-1295 is a synthetic peptide analog of growth hormone-releasing hormone, constructed on the 29-amino-acid fragment designated GRF(1-29). The name began as an internal development code during the 1990s and later spread through research supply catalogs and discussion forums. The molecule does not occur in nature; its sequence is engineered rather than isolated from tissue. Two related compounds are sold under this single label, and they differ by one appended chemical group that strongly influences how long the peptide remains in circulation.
The dividing feature between the two forms is a maleimide-based drug affinity complex, abbreviated DAC. In the DAC-bearing version, a linker attaches the peptide to serum albumin after administration, and that association slows removal from plasma. The version lacking DAC appears in catalogs as MOD GRF(1-29) or tetrasubstituted GRF(1-29). Because informal writing treats both as one item, comparisons drawn from such sources routinely blend measurements taken from two molecules with substantially different behavior.
Four amino acid substitutions separate the modified backbone from the parent GRF(1-29) sequence. These changes reduce recognition by dipeptidyl peptidase IV and related proteases, extending the interval before degradation. Development work in this area sought longer-acting GHRH analogs for endocrine investigation. Published descriptions treat the substitution set as a defining property of the core sequence, while the albumin-binding linker is described separately as an optional addition to that same backbone.
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.
During the experiment, it was determined that the optimal blood-water dilution ratio is 1:2. The blood typing was executed by measuring the ratio of red blood cells (RBC) and plasma transport distances. The accuracy of the proposed PADs in blood typing was 92%, 85%, 89%, 93%, and 96% for A, B, AB, O, and Rh+ blood types respectively.
== Structure == Growth hormone receptor (GHR) is a transmembrane protein consisting of 620 amino acids. The receptor is part of the Type I cytokine receptor family of receptors. GHR exists in two forms as a full length membrane-bound receptor and as a soluble GH binding protein (GHBP). GHR contains two fibronectin type III β domains in its extracellular domain, whereas the intracellular domain contains tyrosine Kinase JAK2 binding sites for SH2 proteins. JAK2 is the primary signal transducer for growth hormone.
=== Second allegation of domestic abuse === About six months after the ATP declined to take action against Zverev, in July 2023, allegations from a second woman became public through a court filing. The public prosecution office requested a penalty order against Zverev in a Berlin criminal court over alleged bodily harm against Brenda Patea, Zverev's ex-girlfriend and the mother of his daughter. On 2 October 2023, the court issued a summary penalty order against Zverev, which included a fine of €450,000. In Germany, summary orders can be issued, typically without a prior hearing, when a judge considers the evidence sufficient to support the accusation and a trial is not deemed necessary. Zverev lodged an objection against the order, which under German law resulted in a public trial. Patea spoke publicly for the first time about the alleged abuse on 1 November 2023 in an interview with the Süddeutsche Zeitung. She said that during a dispute in May 2020, Zverev pushed her into a wall and choked her. In January 2024, Zverev was appointed to serve on the ATP Players Advisory Council. The ATP has been criticized for allowing him to serve on the council while the domestic abuse charge is pending in a criminal court. Also in January 2024, Zverev was featured on the second season of the Netflix series Break Point in an episode focused on his comeback from injury. Netflix was criticized for ignoring both allegations of domestic abuse. One columnist argued that "Break Point promised to take viewers behind the curtain of professional tennis and reveal the personalities behind it.
Although the Cossacks were sometimes portrayed by Bolsheviks, and later by émigré historians, as a monolithic counterrevolutionary group during the civil war, there were many Cossacks who fought with the Red Army throughout the conflict, known as Red Cossacks. Many poorer Cossack communities also remained receptive to the communist message. In late 1918 and early 1919, widespread desertion and defection among Don, Ural, and Orenburg Cossacks fighting with the Whites produced a military crisis that was exploited by the Red Army in those sectors. After the main White armies were defeated in early 1920, many Cossack soldiers switched their allegiance to the Bolsheviks, and fought with the Red Army against the Poles and in other operations. On 22 December 1917, the Council of People's Commissars effectively abolished the Cossack estate by ending their military service requirements and privileges. After the widespread anticommunist rebellions among Cossacks in 1918, the Soviet regime's approach hardened in early 1919, when the Red Army occupied Cossack districts in the Urals and northern Don. The Bolsheviks embarked on a policy of "de-Cossackization", intended to end the Cossack threat to the Soviet regime. This was pursued through resettlement, widespread executions of Cossack veterans from the White armies, and favoring the outlanders within the Cossack hosts. Ultimately, the de-Cossackization campaign led to a renewed rebellion among Cossacks in Soviet-occupied districts and produced a new round of setbacks for the Red Army in 1919.
Sources: en.wikipedia.org
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== Application in surface science == Static SIMS has been used in the investigation of the initial process of oxidation where only the first two or three metal layers participate in the oxidation. Static SIMS gives a rigorous test of surface cleanliness, as it can detect species at ppm concentrations. Static SIMS is used in the investigation of the nature of adsorption (molecular or dissociative). For example, dissociative adsorption of CO on a metal surface (M) is characterized by MC+, MO+, M2O+, and M2C+ secondary ions (Fe and W), and molecular adsorption is identified by MCO+ and M2CO+ ions (Cu, Pd, Ni and Fe). Similarly, it also helps in the investigation of binding energies, chemical structure of the adsorbate, interaction between adsorbate molecules, and reactivity of adsorbate.
=== Interactions === If people are using sNRI drugs they should not take MAO inhibitors at the same time. That can increase the plasma concentration of NRIs in the body. Beware of taking atomoxetine in combination with:
Sources: en.wikipedia.org
=== First interplanetary probes === From the early 1960s both Cold War adversaries almost simultaneously initiated their own programmes which sought to reach other planets in the Solar System for the first time; namely Venus and Mars.
Pakistan drew around 6.6 million foreign tourists in 2018. Pakistan boasts attractions from mangroves in the south to Himalayan hill stations in the northeast, including ancient Buddhist ruins of Takht-i-Bahi and Taxila, the 5,000-year-old Indus Valley civilisation sites such as Mohenjo-daro and Harappa, and numerous mountain peaks over 7,000 metres (23,000 feet). The northern part of Pakistan boasts numerous old fortresses, showcasing ancient architecture. It encompasses the Hunza and Chitral valleys, where the small pre-Islamic Kalasha community resides, claiming descent from Alexander the Great. Lahore, Pakistan's cultural capital, contains lots of Mughal architecture, including the Badshahi Masjid, the Shalimar Gardens, the Tomb of Jahangir, and the Lahore Fort. Following the 2005 Kashmir earthquake, The Guardian highlighted "The top five tourist sites in Pakistan" to boost tourism, featuring destinations like Taxila, Lahore, the Karakoram Highway, Karimabad, and Lake Saiful Muluk. Festivals and government initiatives aim to promote Pakistan's cultural heritage. In 2015, the World Economic Forum ranked Pakistan 125th out of 141 countries in its Travel & Tourism Competitiveness Report.
==== Key physiological parameters in pharmacokinetics include ==== Half-life (t½) – The time required for the drug's plasma concentration to reduce by half. Volume of distribution (VD) – A theoretical volume that relates the total amount of a drug in the body to its measured concentration in the blood (or plasma). Total Clearance (Cltot) – A theoretical pharmacokinetic parameter that statistically explains the efficiency with which a drug is irreversibly eliminated from the body, quantified as the volume of plasma cleared of the drug per unit of time, typically measured in L/h or mL/min. Area Under the Curve (AUC) – The definite integral of the plasma drug concentration versus time curve from time zero to infinity, which represents the total systemic exposure of the body to a drug overtime (AUC0−∞).
Sources: en.wikipedia.org
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.
The original material included a linker that binds serum albumin. A later variant removed that linker to reduce the duration of action. Catalogs and papers did not consistently adopt separate names, so both remain widely labeled with the same term.
The amino acid sequence and the presence or absence of the linker group. Mass measured by spectrometry gives an independent check that separates the two forms.
The version carrying the affinity complex bears a maleimide group that binds serum albumin, which extends its circulation time to several days. The version without it lacks this group and clears within roughly half an hour. The two are chemically related but behave very differently once in the body.