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Cipralisant
Cipralisant (GT-2331, tentative trade name Perceptin) is an extremely potent histamine H3 receptor ligand originally developed by Gliatech. Cipralisant was initially classified as a selective H3 antagonist, but newer research (2005) suggests also agonist properties, i. e. functional selectivity. Cipralisant seemed to be well tolerated during early testing, entering Phase II trials for ADHD in 2000.Evaluate groupGliatech Announces Initiation of Perceptin Phase II Clinical Trial The relatively recent cloning of human H3 receptor, as well as the discovery of its constitutive activity provided the ability to better assess the activity of H3 receptor ligands. Consequently, cipralisant was reassessed as an H3 receptor agonist in human and rat recombinant systems, showing functional selectivity and stimulating one type of G-protein coupled pathway while failing to activate other intracellular pathways. Gliatech filed for bankruptcy in 2002, and its intellectual property was inhe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine H3 Receptor
Histamine H3 receptors are expressed in the central nervous system and to a lesser extent the peripheral nervous system, where they act as autoreceptors in presynaptic histaminergic neurons and control histamine turnover by feedback inhibition of histamine synthesis and release. The H3 receptor has also been shown to presynaptically inhibit the release of a number of other neurotransmitters (i.e. it acts as an inhibitory heteroreceptor) including, but probably not limited to dopamine, Gamma-aminobutyric acid, GABA, acetylcholine, noradrenaline, histamine and serotonin. The gene sequence for H3 receptors expresses only about 22% and 20% homology with both H1 and H2 receptors respectively. There is much interest in the histamine H3 receptor as a potential therapeutic target because of its involvement in the neuronal mechanism behind many cognitive disorders and especially its location in the central nervous system.Rapanelli, Maximiliano. “The Magnificent Two: Histamine and the H3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptor Antagonist
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins.Pharmacology Guide: In vitro pharmacology: concentration-response curves " '' GlaxoWellcome.'' Retrieved on December 6, 2007. They are sometimes called blockers; examples include alpha blockers, |
Agonist
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the agonist, while an inverse agonist causes an action opposite to that of the agonist. Etymology From the Greek αγωνιστής (agōnistēs), contestant; champion; rival < αγων (agōn), contest, combat; exertion, struggle < αγω (agō), I lead, lead towards, conduct; drive Types of agonists can be activated by either endogenous agonists (such as |
Functional Selectivity
Functional selectivity (or “agonist trafficking”, “biased agonism”, “biased signaling”, "ligand bias" and “differential engagement”) is the ligand-dependent selectivity for certain signal transduction pathways relative to a reference ligand (often the endogenous hormone or peptide) at the same receptor. Functional selectivity can be present when a receptor has several possible signal transduction pathways. To which degree each pathway is activated thus depends on which ligand binds to the receptor. Functional selectivity, or biased signaling, is most extensively characterized at G protein coupled receptors (GPCRs). A number of biased agonists, such as those at muscarinic M2 receptors tested as analgesics or antiproliferative drugs, or those at opioid receptors that mediate pain, show potential at various receptor families to increase beneficial properties while reducing side effects. For example, pre-clinical studies with G protein biased agonists at the μ-opioid re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADHD
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by excessive amounts of inattention, hyperactivity, and impulsivity that are pervasive, impairing in multiple contexts, and otherwise age-inappropriate. ADHD symptoms arise from executive dysfunction, and emotional dysregulation is often considered a core symptom. In children, problems paying attention may result in poor school performance. ADHD is associated with other neurodevelopmental and mental disorders as well as some non-psychiatric disorders, which can cause additional impairment, especially in modern society. Although people with ADHD struggle to focus on tasks they are not particularly interested in completing, they are often able to maintain an unusually prolonged and intense level of attention for tasks they do find interesting or rewarding; this is known as hyperfocus. The precise causes of ADHD are unknown in the majority of cases. Genetic factors play an import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal Transduction
Signal transduction is the process by which a chemical or physical signal is transmitted through a cell as a series of molecular events, most commonly protein phosphorylation catalyzed by protein kinases, which ultimately results in a cellular response. Proteins responsible for detecting stimuli are generally termed receptors, although in some cases the term sensor is used. The changes elicited by ligand binding (or signal sensing) in a receptor give rise to a biochemical cascade, which is a chain of biochemical events known as a signaling pathway. When signaling pathways interact with one another they form networks, which allow cellular responses to be coordinated, often by combinatorial signaling events. At the molecular level, such responses include changes in the transcription or translation of genes, and post-translational and conformational changes in proteins, as well as changes in their location. These molecular events are the basic mechanisms controlling cell growth, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merck & Co
Merck & Co., Inc. is an American multinational pharmaceutical company headquartered in Rahway, New Jersey, and is named for Merck Group, founded in Germany in 1668, of whom it was once the American arm. The company does business as Merck Sharp & Dohme or MSD outside the United States and Canada. Merck & Co. was originally established as the American affiliate of Merck Group in 1891. Merck develops and produces medicines, vaccines, biologic therapies and animal health products. It has multiple blockbuster drugs or products each with 2020 revenues including cancer immunotherapy, anti-diabetic medication and vaccines against HPV and chickenpox. The company is ranked 71st on the 2022 ''Fortune'' 500 and 87th on the 2022 ''Forbes'' Global 2000, both based on 2021 revenues. Products The company develops medicines, vaccines, biologic therapies and animal health products. In 2020, the company had 6 blockbuster drugs or products, each with over $1 billion in revenue: ''Keytruda'' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopropanes
Cyclopropane is the cycloalkane with the molecular formula (CH2)3, consisting of three methylene groups (CH2) linked to each other to form a ring. The small size of the ring creates substantial ring strain in the structure. Cyclopropane itself is mainly of theoretical interest but many of its derivatives are of commercial or biological significance. History Cyclopropane was discovered in 1881 by August Freund, who also proposed the correct structure for the substance in his first paper. Freund treated 1,3-dibromopropane with sodium, causing an intramolecular Wurtz reaction leading directly to cyclopropane. The yield of the reaction was improved by Gustavson in 1887 with the use of zinc instead of sodium. Cyclopropane had no commercial application until Henderson and Lucas discovered its anaesthetic properties in 1929; industrial production had begun by 1936. In modern anaesthetic practice, it has been superseded by other agents. Anaesthesia Cyclopropane was introduced into clin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine Agonists
A histamine agonist is a drug which causes increased activity at one or more of the four histamine receptor subtypes. H2: Betazole and Impromidine are examples of agonists used in diagnostics to increase histamine. H3: Betahistine is a weak Histamine1 agonist and a very strong Histamine3 antagonist (paradoxically histamine increasing). See also * Histamine antagonist Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ... External links * * {{pharmacology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
