This is a working overview of GHRH analog, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
Purity is most often assessed by reversed-phase high-performance liquid chromatography, reported as a percentage of total peak area. Identity is confirmed by mass spectrometry, which yields a molecular ion consistent with the expected sequence. Amino acid analysis and peptide mapping provide additional characterization. Reported purity values are method-dependent, so figures from different laboratories are not always directly comparable without details of column, gradient, and detection wavelength.
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.
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.
| 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 |
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.
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.
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.
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.
It can also be produced by oxidising the ephedrine analogue 4-methylephedrine using potassium permanganate dissolved in sulfuric acid. Because 4-methylephedrine can be obtained in a specific enantiomeric form, mephedrone consisting of only one enantiomer can be produced. The danger associated with this method is it may cause manganese poisoning if the product is not correctly purified.
== Tables == The following tables give the elements with primordial nuclides (half-life of most stable isotope > 108 years). A list of nuclides sorted by half-life is found instead at List of nuclides. The tables of elements are sorted by decreasing number of nuclides per element. Stable and unstable nuclides are given, with symbols for the unstable ones in italics. All the primordial isotopes of each element are given in order of decreasing abundance on Earth, regardless of stability. By convention, nuclides are counted as "stable" if they have never been observed to decay by experiment or from observation of decay products (so that nuclides unstable in theory, such as tantalum-180m, are counted as stable). The first table is for even-atomic numbered elements, which tend to have far more primordial nuclides, due to the stability conferred by proton pairing. A second separate table is given for odd-atomic numbered elements, which tend to have far fewer stable and long-lived nuclides.
Phenylpropanolamine (PPA; Accutrim; β-hydroxyamphetamine), also known as the stereoisomers norephedrine and norpseudoephedrine, is a psychoactive drug of the phenethylamine and amphetamine chemical classes that is used as a stimulant, decongestant, and anorectic agent. It is commonly used in prescription and over-the-counter cough and cold preparations. In veterinary medicine, it is used to control urinary incontinence in dogs under trade names Propalin and Proin. In the United States, PPA is no longer sold without a prescription due to a possible increased risk of stroke in younger women. In a few countries in Europe, however, it is still available either by prescription or sometimes over-the-counter. In Canada, it was withdrawn from the market on 31 May 2001. In India, human use of PPA and its formulations were banned on 10 February 2011.
=== DNA repair === Poly(ADP-ribose)polymerases (PARPs) can function in DNA repair of single strand breaks as well as double strand breaks. In single-strand break repair (base excision repair) the PARP can either facilitate removal of an oxidized sugar or strand cleavage. PARP1 binds the single-strand breaks and pulls any nearby base excision repair intermediates close. These intermediates include XRCC1 and APLF and they can be recruited directly or through the PBZ domain of the APLF. This leads to the synthesis of poly(ADP-ribose). The PBZ domain is present in many proteins involved in DNA repair and allows for the binding of the PARP and thus ADP-ribosylation which recruits repair factors to interact at the break site. PARP2 is a secondary responder to DNA damage but serves to provide functional redundancy in DNA repair.
== Synonyms == In the 19th and the early 20th centuries, several synonyms were in use for erythritol: erythrol, erythrite, erythroglucin, eryglucin, erythromannite and phycite. Zerose is a tradename for erythritol.
Sources: en.wikipedia.org
As of 2011, levothyroxine was the second-most commonly prescribed medication in the US, with 23.8 million prescriptions filled each year. In 2023, it was the third most commonly prescribed medication in the United States, with more than 80 million prescriptions.
==== Cannabis effectively outlawed, prescription drugs ==== With the passage of the Marihuana Tax Act of 1937, federal law reflected state law – by 1936, the non-medical use of cannabis had been banned in every state. That year, the first two arrests for tax non-payment under the act, for possession of a quarter-ounce (7g), and trafficking of four pounds (1.8 kg), resulted in sentences of nearly 18 months and four years respectively. The American Medical Association (AMA) had opposed the tax act on grounds that it unduly affected the medical use of cannabis. The AMA's legislative counsel, a physician, testified that the claims about cannabis addiction, violence and overdoses were not supported by evidence. Scholars have posited that the act was orchestrated by powerful business interests – Andrew Mellon, Randolph Hearst, and the Du Pont family – to head off cheap competition to pulp and timber and plastics from the hemp industry. After the act, cannabis research and medical testing became rare. In 1939, New York City Mayor Fiorello LaGuardia, an opponent of the Marihuana Tax Act, formed the LaGuardia Committee to conduct the first US in-depth study of cannabis use. The report, produced by the New York Academy of Medicine and released in 1944, systematically contradicted government claims, finding that cannabis is not physically addictive, and its use does not lead to using other drugs or to crime. The FBN's Anslinger branded the study "unscientific", denounced all involved, and disrupted other cannabis studies at the time.
== Other natriuretic peptides == Humans have three natriuretic peptide (NPPx) genes: NPPA for ANP, NPPB for BNP, and NPPC for CNP. All of these have similar structures and effects. In particular, brain natriuretic peptide (BNP) – a misnomer; it is secreted by ventricular myocytes – is similar to ANP in its effect. It acts via atrial natriuretic peptide receptors but with 10-fold lower affinity than ANP. The biological half-life of BNP, however, is twice as long as that of ANP, and that of NT-proBNP is even longer, making these peptides better choices than ANP for diagnostic blood testing. Alternative cleavages of NPPA produces four peptides with alleged natriuretic properties: long-acting natriuretic peptide (LANP, 26–55), vessel dilator (56–92), kaliuretic peptide (104–123), and urodilatin (120–151). The former two are of a dubious nature. Adrenomedullin, produced by a gene not of the NPPx family, also has a natriuretic property. It works through a different receptor and is generally not considered an NPP. In addition to the mammalian natriuretic peptides (ANP, BNP, CNP), other natriuretic peptides with similar structure and properties have been isolated elsewhere in the animal kingdom. A salmon natriuretic peptide known as salmon cardiac peptide has been described, and dendroaspis natriuretic peptide (DNP) has been found in the venom of the green mamba, as well as an NP in a species of African snake.
== Presentation == Phenotypes of spondyloepiphyseal dysplasia congenita vary. Defining features include short stature, with a short spine and neck, a barrel chest, and normal-sized hands and feet. This type of dwarfism is characterized by a normal spinal column length relative to the femur bone. Adult height ranges from 0.9 meters (35 inches) to just over 1.4 meters (55 inches). Curvature of the spine (such as kyphoscoliosis and lordosis) progresses during childhood and can cause problems with breathing. Changes in the spinal bones (vertebrae) in the neck may also increase the risk of spinal cord damage. Other skeletal signs include flattened vertebrae (platyspondyly), a hip joint deformity in which the upper leg bones turn inward (coxa vara), and an inward- and downward-turning foot (called clubfoot). Decreased joint mobility and arthritis often develop early in life. Medical texts often state a mild and variable change to facial features, including cheekbones close to the nose appearing flattened, although this appears to be unfounded. Some infants are born with a cleft palate. Severe nearsightedness (high myopia) is sometimes present, as are other eye problems that can affect vision such as detached retinas. About one-quarter of people with this condition have mild to moderate hearing loss.
Development of facial wrinkles is a kind of fibrosis of the skin. Misrepair-accumulation aging theory suggests that wrinkles develop from incorrect repairs of injured elastic fibers and collagen fibers. Repeated extensions and compressions of the skin cause repeated injuries of extracellular fibers in derma. During the repairing process, some of the broken elastic fibers and collagen fibers are not regenerated and restored but replaced by altered fibers. When an elastic fiber is broken in an extended state, it may be replaced by a "long" collagen fiber. Accumulation of "long" collagen fibers makes part of the skin looser and stiffer, and as a consequence, a big fold of skin appears. When a "long" collagen is broken in a compressed state, it may be replaced by a "short" collagen fiber. The "shorter" collagen fibers will restrict the extension of "longer" fibers, and make the "long" fibers in a folding state permanently. A small fold, namely a permanent wrinkle, then appears.
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.
Mass spectrometry establishes whether the observed molecular weight matches the calculated sequence mass. Chromatographic retention and fragment mapping add further confidence about sequence and composition. A single technique alone is rarely treated as sufficient evidence of identity.