GHRH analog 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.
Last reviewed on 2026-01-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Peptide degradation proceeds mainly through hydrolysis, oxidation of methionine, and deamidation of asparagine or glutamine residues. The maleimide group on the albumin-binding variant can also react with thiols or hydrolyze in aqueous media. Because these pathways accelerate with temperature and pH extremes, handling conditions strongly influence measured stability. Stability data in the public literature are limited and often generated under differing conditions, so general statements about shelf life should be read as approximate.
Research material is normally supplied as a freeze-dried powder in sealed vials. In that state the peptide is comparatively robust, but prolonged exposure to warmth, moisture, or light accelerates degradation. Storage at minus twenty degrees Celsius or lower, with desiccant and protection from light, is the commonly described practice. Vials should be allowed to reach room temperature before opening to limit condensation on the powder. Moisture uptake during handling is a recognized source of variability in later measurements.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white lyophilized powder | Visual descriptor; not a measure of purity |
| Solubility class | Freely soluble in water | Aqueous dissolution may require gentle mixing |
| Typical storage (powder) | −20 °C or below, desiccated | Protect from light and ambient moisture |
| Typical storage (solution) | 2–8 °C, short term | Freeze aliquots where longer holding is needed |
| Purity assessment | Reversed-phase HPLC, area percent | Values depend on column, gradient, and detection wavelength |
Stability depends heavily on physical state. A lyophilized powder kept dry, desiccated, and shielded from light typically holds its integrity for months to years at minus twenty degrees Celsius, and longer at minus eighty. Once dissolved, the peptide becomes far more vulnerable, since peptide bond hydrolysis, oxidation of susceptible residues, and aggregation all proceed faster in solution. Buffers near neutral pH are generally gentler than strongly acidic or alkaline conditions. Repeated freeze-thaw cycles and exposure to air-liquid interfaces during vigorous mixing cause losses that are easy to overlook.
Verification matters because research peptides vary widely in quality. A certificate of analysis is only as reliable as the method behind it, and a single chromatographic trace reveals little about counter-ions, residual solvents, or water content. Independent laboratories commonly pair mass confirmation with chromatographic purity and, where relevant, quantify water along with acetate or trifluoroacetate content. Reported purity figures are not standardized across suppliers, so a stated value such as ninety-eight percent is not directly comparable unless the analytical method, column, and detection wavelength accompany it.
Characterization of this peptide relies on a small set of routine techniques. Reversed-phase high-performance liquid chromatography separates the target from truncated or oxidized by-products and yields a purity estimate when paired with ultraviolet detection near 214 nanometers. Mass spectrometry, either electrospray coupled to liquid chromatography or matrix-assisted laser desorption, confirms that the observed mass matches the value calculated for the expected sequence. Amino acid analysis, and enzymatic digestion followed by fragment mapping, are used when the sequence itself rather than the mass requires verification.
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 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.
The International Union of Pure and Applied Chemistry (IUPAC) initially established lawrencium as the official name for the element and gave the American team credit for the discovery; this was reevaluated in 1992, giving both teams shared credit for the discovery but not changing the element's name.
== External links == Apelin+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH) "Apelin". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Archived from the original on 2021-08-16. Retrieved 2007-10-25. Human APLN genome location and APLN gene details page in the UCSC Genome Browser.
John Russell (1893–1917), recipient of the Victoria Cross, born in Holyhead Ceinwen Rowlands (1905–1983), a Welsh concert soprano and recording artist, born in Holyhead R. S. Thomas (1913–2000), a Welsh poet and Anglican priest poet, grew up in Holyhead Cledwyn Hughes, Baron Cledwyn of Penrhos (1916–2001) MP & politician, born in Holyhead, attended Ysgol Uwchradd Caergybi Barbara Margaret Trimble (1921–1995) a British writer of over 20 crime, thriller and romance novels, born in Holyhead David Crystal (born 1941) linguist and chair of the charity behind Holyhead's Ucheldre Centre, lives in Holyhead Glenys Kinnock (1944-2023) a politician, MEP, educated at Holyhead High School Dawn French (born 1957 in Holyhead) comedian and actress, co-star in French and Saunders Albert Owen (born 1959 in Holyhead) politician, MP for Ynys Môn from 2001 to 2019. Kevin Johnson (born 1960 in Holyhead), a managing partner at Medicxi Ventures, a venture capital firm Jason Evans (born 1968 in Holyhead), a Welsh photographer and lecturer on photography Ben Crystal (born 1977), an English actor, author, and producer brought up in Holyhead Gareth Williams (1978–2010) worked for GCHQ and SIS died in suspicious circumstances
Sources: en.wikipedia.org
Historically, American black bears occupied the majority of North America's forested regions. Today, they are primarily limited to sparsely settled, forested areas. American black bears currently inhabit much of their original Canadian range, though they seldom occur in the southern farmlands of Alberta, Saskatchewan and Manitoba; they have been extirpated on Prince Edward Island since 1937. Surveys taken in the mid-1990s found the Canadian black bear population to be between 396,000 and 476,000 in seven provinces; this estimate excludes populations in New Brunswick, the Northwest Territories, Nova Scotia and Saskatchewan. All provinces indicated stable populations of American black bears over the 2000s. The current range in the United States is constant throughout most of the Northeast and within the Appalachian Mountains almost continuously from Maine to northern Georgia, the northern Midwest, the Rocky Mountain region, the West Coast and Alaska. However, it becomes increasingly fragmented or absent in other regions. Despite this, American black bears in those areas seem to have expanded their range in recent decades, such as with sightings in Ohio, Illinois, southern Indiana, and western Nebraska. Sightings of itinerant black bears in the Driftless Area of southeastern Minnesota, northeastern Iowa, and southwestern Wisconsin are common.
== Characteristics == The genome of C. xerosis is approximately 2.7 million base pairs long with over 2,000 genes encoding proteins and a high G+C content. C. xerosis was found to contain a series of plasmids, one of which confers resistance to common antibiotics such as chloramphenicol, kanamycin, streptomycin, and tetracycline and was named pTP10. This plasmid has since been introduced into Bacillus subtilis and modified to generate several vectors for molecular cloning purposes. In addition to having resistance to many antibiotics itself, at least one strain of C. xerosis also appears capable of producing antimicrobial compounds. These can inhibit bacteria and fungi, but the strength of antimicrobial activity by this strain depends on the carbon sources available. Also, a petroleum ether extract from C. xerosis was found to decrease the growth rate of tumors in mice, increasing their lifespan while being nontoxic to healthy mice. A study in 1967 confirmed the ability of several strains of C. xerosis to form single-layer "clumps" of cells around gas bubbles when cultures of the bacteria are suspended in buffer solutions at low temperatures with vigorous stirring. This property was attributed to cell surface proteins.
Immunomodulators Inhibitors of protein kinases Opioids Analgesics Treatment of benign prostatic hyperplasia Antiadrenergic drugs Hormonal treatments Diuretics Antiretroviral therapy Antihistamines Antidepressants *"For most of the drugs that are likely to affect spermatogenesis and/or sperm parameters, the levels of scientific evidence are still insufficient (with the exception of Sirolimus, Sulfasalazine, exogenous testosterone, Finasteride and Cyproterone acetate, for which the levels of evidence are higher). In some cases, data in men do not even exist, and the toxicity of a drug for the male reproductive organs is determined solely on the basis of animal models." **"For a certain number of pharmaceutical molecules that are likely to affect the sexual function of men being treated, the actual imputability of the drug is often difficult to pinpoint owing to the effect of the illness itself on sexuality (cardiovascular disease and erectile dysfunction; depressive illness and loss of desire, etc.)" Furthermore, hyperthyroidism, an excess of thyroid hormones, has been associated with reduced semen volume, reduced sperm density, motility, and morphology. Studies in humans show that an excess of circulating thyroid hormones during thyrotoxicosis results in asthenozoospermia, oligozoospermia, and teratozoospermia. These abnormalities frequently associate with semen alterations like reduced semen volume.
== Further reading == Archives National Library of Scotland, correspondence and papers The National Archives Public Record Office (TNA: PRO), reports on Germany, MH79/358 National Archives of Scotland, correspence with Lord Lothian Rowett Research Institute, Aberdeenshire, corresp. and papers relating to Rowett Research Institute Likenesses from the National Portrait Gallery Lida Moser, photograph, 1949, National Portrait Gallery (NPG) [see illus.] B. Schotz, bronze head, 1950, Hunterian Museum and Art Gallery, Glasgow W. Stoneman, bromide print, 1953, NPG Elliott & Fry, photograph, NPG Elliott & Fry, vintage print, 1942, NPG photograph, repro. in Kay, Memoirs FRS Hansard 1803–2005: contributions in Parliament by John Boyd Orr
Sources: en.wikipedia.org
Cool, dark, and dry conditions are standard, with storage at minus twenty degrees Celsius or below. Desiccant and sealed vials limit moisture uptake. Repeated warming and cooling of the container is generally avoided.
There is no single agreed limit, and laboratory practice varies widely. Refrigeration slows degradation, and freezing aliquots is often described for longer holding. Any visible cloudiness or precipitate indicates the solution should be discarded.
Mass spectrometry provides the most direct confirmation through molecular mass. Reversed-phase chromatography supports purity assessment, and peptide mapping or amino acid analysis can corroborate sequence. No single method establishes both purity and identity on its own.
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.