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Gliotransmission
Gliotransmitters are chemicals released from glial cells that facilitate communication between glial cells and neurons. They are usually induced from Ca2+ signaling, although recent research has questioned the role of Ca2+ in gliotransmitters and may require a revision of the relevance of gliotransmitters in neuronal signalling in general. While gliotransmitters can be released from any glial cell, they are primarily released from astrocytes. Astrocytes rely on gap junctions for coupling, and are star-like in shape, which allows them to come into contact with many other synapses in various regions of the brain. Their structure also makes them capable of bidirectional signaling. It is estimated that astrocytes can make contact with over 100,000 synapses, allowing them to play an essential role in synaptic transmission. While gliotransmission primarily occurs between astrocytes and neurons, gliotransmission is not limited to these two cell types. Besides the central nervous system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a Chemical synapse, synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they are able to interact with neurotransmitter receptors on the target cell. Some neurotransmitters are also stored in large dense core vesicles. The neurotransmitter's effect on the target cell is determined by the receptor it binds to. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available and often require a small number of biosynthetic steps for conversion. Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified. Common neurotransmitters include Glutamate (neurotransmi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glial Cells
Glia, also called glial cells (gliocytes) or neuroglia, are non-neuronal cells in the central nervous system (the brain and the spinal cord) and in the peripheral nervous system that do not produce electrical impulses. The neuroglia make up more than one half the volume of neural tissue in the human body. They maintain homeostasis, form myelin, and provide support and protection for neurons. In the central nervous system, glial cells include oligodendrocytes (that produce myelin), astrocytes, ependymal cells and microglia, and in the peripheral nervous system they include Schwann cells (that produce myelin), and satellite cells. Function They have four main functions: * to surround neurons and hold them in place * to supply nutrients and oxygen to neurons * to insulate one neuron from another * to destroy pathogens and remove dead neurons. They also play a role in neurotransmission and synaptic connections, and in physiological processes such as breathing. While glia wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemicals
A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combined without reacting, they may form a chemical mixture. If a mixture is separated to isolate one chemical substance to a desired degree, the resulting substance is said to be chemically pure. Chemical substances can exist in several different physical states or phases (e.g. solids, liquids, gases, or plasma) without changing their chemical composition. Substances transition between these phases of matter in response to changes in temperature or pressure. Some chemical substances can be combined or converted into new substances by means of chemical reactions. Chemicals that do not possess this ability are said to be inert. Pure water is an example of a chemical substance, with a constant composition of two hydrogen atoms bonded to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gap Junction
Gap junctions are membrane channels between adjacent cells that allow the direct exchange of cytoplasmic substances, such small molecules, substrates, and metabolites. Gap junctions were first described as ''close appositions'' alongside tight junctions, however, electron microscopy studies in 1967 led to gap junctions being named as such to be distinguished from tight junctions. They bridge a 2-4 nm gap between cell membranes. Gap junctions use protein complexes known as connexons, composed of connexin proteins to connect one cell to another. Gap junction proteins include the more than 26 types of connexin, as well as at least 12 non-connexin components that make up the gap junction complex or ''nexus,'' including the tight junction protein ZO-1—a protein that holds membrane content together and adds structural clarity to a cell, sodium channels, and aquaporin. More gap junction proteins have become known due to the development of next-generation sequencing. Connexins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schwann Cells
Schwann cells or neurolemmocytes (named after German physiologist Theodor Schwann) are the principal glia of the peripheral nervous system (PNS). Glial cells function to support neurons and in the PNS, also include Satellite glial cell, satellite cells, olfactory ensheathing cells, enteric glia and glia that reside at sensory nerve endings, such as the Pacinian corpuscle. The two types of Schwann cells are Myelin, myelinating and Nonmyelinating Schwann cell, nonmyelinating. Myelinating Schwann cells wrap around axons of motor and sensory neurons to form the myelin sheath. The Schwann cell promoter is present in the Upstream and downstream (DNA), downstream region of the human dystrophin gene that gives shortened Transcription (biology), transcript that are again synthesized in a tissue-specific manner. During the development of the PNS, the regulatory mechanisms of myelination are controlled by feedforward interaction of specific genes, influencing transcriptional cascades and sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Müller Cells
Müller may refer to: Companies * Müller (company), a German multinational dairy company ** Müller Milk & Ingredients, a UK subsidiary of the German company * Müller (store), a German retail chain * GMD Müller, a Swiss aerial lift manufacturing company Places * Müller Glacier, Antarctica * Müller Mountains, Borneo * Müller Point, on the east coast of South Georgia * Müller (lunar crater) * Müller (Martian crater) * Müller House, a historic house in Arlington Heights, Illinois, U.S. People and characters * Müller (surname) The German word Müller () means "miller" (as a profession). It is the most common family surname in Germany, Switzerland, and the French départements of Bas-Rhin and Moselle (department), Moselle (with the spelling Müller, Mueller (surname), Muel ..., a German surname * Müller (footballer, born 1957), José Edmur Lucas Corrêa, Brazilian footballer * Müller (footballer, born 1966), Luís Antônio Corrêa da Costa, Brazilian footballer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamate
Glutamic acid (symbol Glu or E; known as glutamate in its anionic form) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a Essential amino acid, non-essential nutrient for humans, meaning that the human body can synthesize enough for its use. It is also the most abundant excitatory neurotransmitter in the vertebrate nervous system. It serves as the precursor for the synthesis of the inhibitory gamma-aminobutyric acid (GABA) in GABAergic neurons. Its molecular formula is . Glutamic acid exists in two optically isomeric forms; the optical rotation, dextrorotatory -form is usually obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation.Webster's Third New International Dictionary of the English Language Unabridged, Third Edition, 1971. Its molecular structure could be idealized as HOOC−CH()−()2−COOH, with two carboxylic acid, carboxyl groups −COOH and one amine, amino group � ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is a nucleoside triphosphate that provides energy to drive and support many processes in living cell (biology), cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all known forms of life, it is often referred to as the "molecular unit of currency" for intracellular energy transfer. When consumed in a Metabolism, metabolic process, ATP converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. It is also a Precursor (chemistry), precursor to DNA and RNA, and is used as a coenzyme. An average adult human processes around 50 kilograms (about 100 mole (unit), moles) daily. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of three parts: a sugar, an amine base ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SNARE
SNARE proteins – "Soluble NSF attachment protein, SNAP REceptors" – are a large protein family consisting of at least 24 members in yeasts and more than 60 members in mammalian and plant cells. The primary role of SNARE proteins is to mediate the vesicle fusion, fusion of vesicles with the target Cell membrane, membrane; this notably mediates exocytosis, but can also mediate the fusion of vesicles with membrane-bound compartments (such as a lysosome). The best studied SNAREs are those that mediate the release of synaptic vesicles containing neurotransmitters in neurons. These neuronal SNAREs are the targets of the neurotoxins responsible for botulism and tetanus produced by certain bacteria. Types SNAREs can be divided into two categories: ''vesicle'' or ''v-SNAREs'', which are incorporated into the membranes of transport vesicles during budding, and ''target'' or ''t-SNAREs'', which are associated with nerve terminal membranes. Evidence suggests that t-SNAREs form s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homocysteic Acid
Homocysteic acid is the organosulfur compound with the formula . A white solid, it is sulfonic acid-containing non-proteinogenic amino acid. It is a analog of glutamic acid and is a potent NMDA receptor agonist. It is related to homocysteine, a by-product of methionine metabolism. Homocysteic acid is prepared by the oxidation of homocystine with aqueous bromine Bromine is a chemical element; it has chemical symbol, symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between th .... References Alpha-Amino acids Sulfonic acids NMDA receptor agonists {{OrganicAcid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NMDA
''N''-methyl--aspartic acid, or ''N''-methyl--aspartate (NMDA), is an amino acid derivative that acts as a specific agonist at the NMDA receptor mimicking the action of glutamate, the neurotransmitter which normally acts at that receptor. Unlike glutamate, NMDA only binds to and regulates the NMDA receptor and has no effect on other glutamate receptors (such as those for AMPA and kainate). NMDA receptors are particularly important when they become overactive during, for example, alcohol withdrawal, as this causes symptoms such as agitation and, sometimes, epileptiform seizures. Biological function In 1962, J.C. Watkins reported synthesizing NMDA, an isomer of the previously known ''N''-Methyl--aspartic-acid. NMDA is a water-soluble -alpha-amino acid — an aspartic acid derivative with an ''N''-methyl substituent and - configuration — found across Chordates from lancelets to mammals. At homeostatic levels NMDA plays an essential role as a neurotransmitter and neuroen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taurine
Taurine (), or 2-aminoethanesulfonic acid, is a naturally occurring amino sulfonic acid that is widely distributed in animal tissues. It is a major constituent of bile and can be found in the large intestine. It is named after Latin (cognate to Ancient Greek , ) meaning bull or ox, as it was first isolated from ox bile in 1827 by German scientists Friedrich Tiedemann and Leopold Gmelin. It was identified in human bile in 1846 by Edmund Ronalds. Although taurine is abundant in human organs, it is not an essential human dietary nutrient and is not included among nutrients with a recommended intake level. Among the diverse pathways by which natural taurine can be biosynthesized, its human pathways (primarily in the human liver) are from cysteine and/or methionine. Taurine is commonly sold as a dietary supplement, but there is no good clinical evidence that taurine supplements provide any benefit to human health. Taurine is used as a food additive for cats (who require ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
