This is a working overview of Mod GRF(1-29), written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-03-02. 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.
CJC-1295 is a synthetic peptide designed to mimic growth hormone-releasing hormone (GHRH), the endogenous signal that prompts the pituitary gland to release growth hormone. The compound is a modified fragment of the natural hormone, spanning the first twenty-nine amino acids of GHRH with several substitutions that slow enzymatic breakdown. Two variants circulate in research settings: one carrying a drug affinity complex (DAC) and one without it. The DAC-free form is frequently labelled Mod GRF(1-29) in catalogs and discussion forums.
The peptide binds GHRH receptors on somatotroph cells within the anterior pituitary, triggering a signalling cascade that increases growth hormone secretion. Its improved resistance to dipeptidyl peptidase IV degradation distinguishes it from the parent hormone. In the DAC-bearing version, a maleimide group reacts with a cysteine residue on serum albumin, forming a covalent bond that keeps the peptide in circulation far longer. That albumin attachment is the central design feature separating the two research variants.
| 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 |
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.
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.
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.
== Personal life == Beginning in 2016, Chase retired from the entertainment industry. According to Chase's former manager John Ryan, Chase had a scheduled meeting with director Rob Reiner for a film project in November 2015, but failed to appear at the venue. Ryan cited this as the start of her "disappearance"; Chase had no contact with any of her family and friends after the failed meeting. In her final years, Chase had reportedly living on the streets of Skid Row and downtown Los Angeles. According to her mother, Chase had suffered from drug addiction since about 2016, when she was prescribed painkillers after a motorcycle accident severely injured her back. However, her father claimed that Chase had suffered from drug addiction since the age of 13 (around 2003 or 2004). In November 2017, Chase was arrested in Los Angeles on a felony charge after being found riding as a passenger in a vehicle that had been reported stolen. Eight months earlier in February 2017, Chase was detained by LAPD detectives and questioned after she was seen leaving an unresponsive man at a local hospital, who was subsequently pronounced dead of a suspected drug overdose. In August 2018, Chase was arrested by the LAPD on a misdemeanor charge of drug possession and spent a short time in a Hollywood jail before being released on a $1,000 bond. By November 2018, she was charged with two misdemeanor counts stemming from these incidents: possession of a controlled substance without a valid prescription and possession of drug paraphernalia.
=== US 1938–1947 === Eltenton was an open admirer of the USSR and its people. Both he and his wife gave lectures at the California Labor School on Russian life, and were active in the American Russian Institute. He was also a trade union activist for the Federation of Architects, Engineers, Chemists and Technicians at Shell, and was at a meeting where Robert Oppenheimer encouraged the formation of a section at the Lawrence Berkeley National Laboratory. In 1939, with the beginning of the Second World War he contacted the British Embassy to volunteer, but was told his work for the oil company was better use of his talents. In 1941 the USSR was invaded by Germany, and he and his wife became active members of the Russian War Relief organization. In May 1942, after the US had also joined the war and was therefore an ally of the USSR, the Eltentons had Piotr Ivanov, the vice consul of the Soviet consulate in San Francisco as a dinner guest. It was there that Ivanov raised the possibility of atomic research being shared between the US and the USSR, and suggested three scientists who might be prepared to do so, if discretion could be assured. Eltenton was doubtful, but agreed to ask a mutual friend Haakon Chevalier to suggest this to Oppenheimer. Chevalier reported back that Oppenheimer was not interested, but when the fact of the approach was revealed by Oppenheimer in 1946, Eltenton was interviewed by the FBI.
=== Pharmacokinetics === When administered orally in a 70:30 molar ratio, serdexmethylphenidate/dexmethylphenidate produces a dexmethylphenidate plasma concentration profile with a time to maximum concentration Tmax of approximately 2 hours and an mean terminal elimination half-life of 11.7 hours.
Sources: en.wikipedia.org
Muscle weakness can also be classified as either "proximal" or "distal" based on the location of the muscles that it affects. Proximal muscle weakness affects muscles closest to the body's midline, while distal muscle weakness affects muscles further out on the limbs. Proximal muscle weakness can be seen in Cushing's syndrome and hyperthyroidism.
A referendum of the mostly white electorate approved the new constitution by a majority of 65% on 26 July 1961. The final version of the constitution included a few extra provisions inserted by the British, one of which—Section 111—reserved full powers to the Crown to amend, add to or revoke certain sections of the Southern Rhodesian constitution by Order in Council at the request of the British government. This effectively negated the relinquishment of British powers described elsewhere in the document, but the Southern Rhodesians did not initially notice it. The black Rhodesian movement in Southern Rhodesia, founded and organised by urban black elites during the late 1950s, was repeatedly banned by the colonial government because of the political violence, industrial sabotage and intimidation of potential black voters that characterised its campaign. The principal nationalist group, led by the Bulawayo trade unionist Joshua Nkomo, renamed itself with each post-ban reorganisation, and by the start of 1962 was called the Zimbabwe African People's Union (ZAPU). Attempting to win black political support, Whitehead proposed a number of reforms to racially discriminatory legislation, including the Land Apportionment Act, and promised to implement these if his UFP won the next Southern Rhodesian election. Intimidation by ZAPU of prospective black voters impeded the UFP's efforts to win their support and caused low turnout, but regardless, the UFP won 14 of 15 primarily black seats in the December 1962 Southern Rhodesian election.
=== Competitive and ecological roles === Beyond these interactions, Xanthoria parietina often overgrows other epilithic lichens without affecting their photobionts. It also supports microbial communities beneath its thallus, likely benefiting from microhabitats created by its attachment structures. In addition, Xanthoria parietina plays a role in biogeochemical cycling by promoting rock weathering through hyphal penetration and adhesion. Its interactions with minerals such as quartz, feldspar, and muscovite contribute to mineral breakdown, particularly in carbonate-rich substrates. Finally, the lichen competes with other foliose lichens. In experimental settings, it showed competitive equivalence with Parmelia caperata but was overgrown by Parmelia saxatilis under some conditions. In three-species mixtures, however, X. parietina often gained a competitive advantage—possibly due to its tolerance for elevated nitrogen levels. Its ability to thrive in nutrient-rich environments may allow it to outcompete acidophytic species in habitats influenced by agricultural or atmospheric nitrogen inputs. When competing with other lichens, X. parietina typically forms codominant relationships rather than completely displacing other species, particularly in early colonization stages. Field studies show that when X. parietina thalli border upon other lichens such as Physcia species, neither distinctly overgrows the other, but rather their marginal lobes intermingle. The frequent co-occurrence of X. parietina with grey-colored Physcia species may represent more than simple cohabitation.
==== Germany ==== Various pseudoephedrine-containing products in combination with ibuprofen, aspirin, or antihistamines can be obtained without a prescription upon request at a pharmacy. Common names include Aspirin Complex, Reactine Duo, and RhinoPront. Products containing pseudoephedrine as a single ingredient are not available.
Sources: en.wikipedia.org
== Formation and morphology == During embryonic development, the anterior and posterior pituitary merge due to regulated cell-to-cell interactions, signaling pathways, and numerous transcription factors. Of the pituitary endocrine cells, the gonadotropic cells are the last to form and become functional. It has been found through studies with zebrafish that glycoprotein 𝞪-subunit (gpa) and thyroid-stimulating hormone beta (tshb) expressing cells are precursors for gonadotropes and thyrotropes. Even further, the genes involved in the final differentiation of these precursors into gonadotropes are sine oculus 1 (six1), eyes absent homolog 1 (eya1), steroidogenic factor 1 (sf1), and paired-like homeodomain 1 (pitx1).
=== Functioning as signal transducer === Within the last decade, many independent labs have demonstrated that, in addition to the classical ion transporting, this membrane protein can also relay extracellular ouabain-binding signalling into the cell through regulation of protein tyrosine phosphorylation. For instance, a study investigated the function of Na+/K+-ATPase in foot muscle and hepatopancreas in land snail Otala lactea by comparing the active and estivating states. They concluded that reversible phosphorylation can control the same means of coordinating ATP use by this ion pump with the rates of the ATP generation by catabolic pathways in estivating O. lactea. The downstream signals through ouabain-triggered protein phosphorylation events include activation of the mitogen-activated protein kinase (MAPK) signal cascades, mitochondrial reactive oxygen species (ROS) production, as well as activation of phospholipase C (PLC) and inositol triphosphate (IP3) receptor (IP3R) in different intracellular compartments. Protein-protein interactions play a very important role in Na+-K+ pump-mediated signal transduction. For example, the Na+-K+ pump interacts directly with Src, a non-receptor tyrosine kinase, to form a signaling receptor complex. Src is initially inhibited by the Na+-K+ pump. However, upon subsequent ouabain binding, the Src kinase domain is released and then activated. Based on this scenario, NaKtide, a peptide Src inhibitor derived from the Na+-K+ pump, was developed as a functional ouabain–Na+-K+ pump-mediated signal transduction.
Dermal fibroblasts are cells within the dermis layer of skin which are responsible for generating connective tissue and allowing the skin to recover from injury. Using organelles (particularly the rough endoplasmic reticulum), dermal fibroblasts generate and maintain the connective tissue which unites separate cell layers. Furthermore, these dermal fibroblasts produce the protein molecules including laminin and fibronectin which comprise the extracellular matrix. By creating the extracellular matrix between the dermis and epidermis, fibroblasts allow the epithelial cells of the epidermis to affix the matrix, thereby allowing the epidermal cells to effectively join together to form the top layer of the skin.
MELAS (Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes) is one of the family of mitochondrial diseases, which also include MIDD (maternally inherited diabetes and deafness), MERRF syndrome, and Leber's hereditary optic neuropathy. It was first characterized under this name in 1984. A feature of these diseases is that they are caused by defects in the mitochondrial genome which is inherited purely from the female parent. The most common MELAS mutation is one in mitochondrial DNA (mtDNA) referred to as m.3243A>G.
=== Pharmacodynamics === Butane-1,4-diol seems to have two types of pharmacological actions. The major psychoactive effects of 1,4-butanediol are because it is metabolized into GHB; however, there is a study suggesting that 1,4-butanediol may have potential alcohol-like pharmacological effects on its own. The study arrived at this conclusion based on the finding that butane-1,4-diol coadministered with ethanol led to potentiation of some of the behavioral effects of ethanol. However, potentiation of ethanol's effects may simply be caused by competition for the alcohol dehydrogenase and aldehyde dehydrogenase enzymes with co-administered 1,4-butanediol. The shared metabolic rate-limiting steps thus leads to slowed metabolism and clearance for both compounds including ethanol's known toxic metabolite acetaldehyde. Another study found no effect following intracerebroventricular injection of butane-1,4-diol in rats. This contradicts the hypothesis of butane-1,4-diol having inherent alcohol-like pharmacological effects. Like gamma-hydroxybutyric acid, butane-1,4-diol is safe only in small amounts. Adverse effects in higher doses include nausea, vomiting, dizziness, sedation, vertigo, and potentially death if ingested in large amounts. Anxiolytic effects are diminished and side effects increased when used in combination with alcohol.
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 synthetic peptide keeps the receptor-binding region of GHRH but carries substitutions that resist enzymatic cleavage. In the DAC version, an added group also anchors the molecule to albumin, extending its presence in the bloodstream.