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GABA Analogues
GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GABA is sold as a dietary supplement in many countries. It has been traditionally thought that exogenous GABA (i.e., taken as a supplement) does not cross the blood–brain barrier, but data obtained from more recent research (2010s) in rats describes the notion as being unclear. The carboxylate form of GABA is γ-aminobutyrate. Function Neurotransmitter Two general classes of GABA receptor are known: * GABAA receptor, GABAA in which the receptor is part of a ligand-gated ion channel complex * GABAB receptor, GABAB metabotropic receptors, which are G protein-coupled receptors that open or close ion channels via intermediaries (G proteins) Neurons that produce GABA as their output are called GABAergic neurons, and have chiefly inhibito ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CRC Press
The CRC Press, LLC is an American publishing group that specializes in producing technical books. Many of their books relate to engineering, science and mathematics. Their scope also includes books on business, forensics and information technology. CRC Press is now a division of Taylor & Francis, itself a subsidiary of Informa. History The CRC Press was founded as the Chemical Rubber Company (CRC) in 1903 by brothers Arthur, Leo and Emanuel Friedman in Cleveland, Ohio, based on an earlier enterprise by Arthur, who had begun selling rubber laboratory aprons in 1900. The company gradually expanded to include sales of laboratory equipment to chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...s. In 1913 the CRC offered a short (116-page) manual called the ''Rubber Handboo ... [...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] |
Neural Development
The development of the nervous system, or neural development (neurodevelopment), refers to the processes that generate, shape, and reshape the nervous system of animals, from the earliest stages of embryonic development to adulthood. The field of neural development draws on both neuroscience and developmental biology to describe and provide insight into the cellular and molecular mechanisms by which complex nervous systems develop, from nematodes and Drosophila melanogaster, fruit flies to mammals. Defects in neural development can lead to malformations such as holoprosencephaly, and a wide variety of neurological disorders including paresis, limb paresis and paralysis, balance and vision disorders, and seizures, and in humans other disorders such as Rett syndrome, Down syndrome and intellectual disability. Vertebrate brain development The vertebrate central nervous system (CNS) is derived from the ectoderm—the outermost germ layer of the embryo. A part of the dorsal ect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neonatal
In common terminology, a baby is the very young offspring of adult human beings, while infant (from the Latin word ''infans'', meaning 'baby' or 'child') is a formal or specialised synonym. The terms may also be used to refer to Juvenile (organism), juveniles of other organisms. A newborn is, in colloquial use, a baby who is only hours, days, or weeks old; while in medical contexts, a newborn or neonate (from Latin, ''neonatus'', newborn) is an infant in the first 28 days after Human birth, birth (the term applies to Preterm birth, premature, Pregnancy#Term, full term, and Postterm pregnancy, postmature infants). Infants born prior to 37 weeks of gestation are called "premature", those born between 39 and 40 weeks are "full term", those born through 41 weeks are "late term", and anything beyond 42 weeks is considered "post term". Before birth, the offspring is called a fetus. The term ''infant'' is typically applied to very young children under one year of age; however, defini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Resistance And Conductance
The electrical resistance of an object is a measure of its opposition to the flow of electric current. Its Multiplicative inverse, reciprocal quantity is , measuring the ease with which an electric current passes. Electrical resistance shares some conceptual parallels with mechanical friction. The International System of Units, SI unit of electrical resistance is the ohm (), while electrical conductance is measured in siemens (unit), siemens (S) (formerly called the 'mho' and then represented by ). The resistance of an object depends in large part on the material it is made of. Objects made of electrical insulators like rubber tend to have very high resistance and low conductance, while objects made of electrical conductors like metals tend to have very low resistance and high conductance. This relationship is quantified by electrical resistivity and conductivity, resistivity or conductivity. The nature of a material is not the only factor in resistance and conductance, howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shunting Inhibition
Shunting inhibition, also known as divisive inhibition, is a form of postsynaptic potential inhibition that can be represented mathematically as reducing the excitatory potential by division, rather than linear subtraction. The term "shunting" is used because of the synaptic conductance short-circuit currents that are generated at adjacent excitatory synapses. If a shunting inhibitory synapse is activated, the input resistance is reduced locally. The amplitude of subsequent excitatory postsynaptic potential (EPSP) is reduced by this, in accordance with Ohm's Law. This simple scenario arises if the inhibitory synaptic reversal potential is identical to or even more negative than the resting potential. Discovery Shunting inhibition was discovered by Fatt and Katz in 1953. Mechanism Shunting inhibition is theorized to be a type of gain control mechanism, regulating the responses of neurons. Simple inhibition such as hyperpolarization has a subtractive effect on the depolar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloride
The term chloride refers to a compound or molecule that contains either a chlorine anion (), which is a negatively charged chlorine atom, or a non-charged chlorine atom covalently bonded to the rest of the molecule by a single bond (). The pronunciation of the word "chloride" is . Chloride salts such as sodium chloride are often soluble in water.Green, John, and Sadru Damji. "Chapter 3." ''Chemistry''. Camberwell, Vic.: IBID, 2001. Print. It is an essential electrolyte located in all body fluids responsible for maintaining acid/base balance, transmitting nerve impulses and regulating liquid flow in and out of cells. Other examples of ionic chlorides include potassium chloride (), calcium chloride (), and ammonium chloride (). Examples of covalent chlorides include methyl chloride (), carbon tetrachloride (), sulfuryl chloride (), and monochloramine (). Electronic properties A chloride ion (diameter 167 pm) is much larger than a chlorine atom (diameter 99 pm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chandelier Cell
Chandelier cells or chandelier neurons are a subset of GABAergic cortical interneurons. They are described as parvalbumin-containing and fast-spiking to distinguish them from other subtypes of GABAergic neurons, although some studies have suggested that only a subset of chandelier cells test positive for parvalbumin by immunostaining. The name comes from the specific shape of their axon arbors, with the terminals forming distinct arrays called "''cartridges''". The cartridges are immunoreactive to an isoform of the GABA membrane transporter, GAT-1, and this serves as their identifying feature. GAT-1 is involved in the process of GABA reuptake into nerve terminals, thus helping to terminate its synaptic activity. Chandelier neurons synapse exclusively to the axonal initial segment of pyramidal neurons, near the site where action potential is generated. It is believed that they provide inhibitory input to the pyramidal neurons, but there is data showing that in some circumstances ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gland
A gland is a Cell (biology), cell or an Organ (biology), organ in an animal's body that produces and secretes different substances that the organism needs, either into the bloodstream or into a body cavity or outer surface. A gland may also function to remove unwanted substances such as urine from the body. There are two types of gland, each with a different method of secretion. Endocrine glands are ductless and secrete their products, hormones, directly into interstitial spaces to be taken up into the bloodstream. Exocrine glands secrete their products through a duct into a body cavity or outer surface. Glands are mostly composed of epithelium, epithelial tissue, and typically have a supporting framework of connective tissue, and a capsule. Structure Development Every gland is formed by an ingrowth from an epithelium, epithelial surface. This ingrowth may in the beginning possess a tubular structure, but in other instances glands may start as a solid column of cells which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons). Nerves have historically been considered the basic units of the peripheral nervous system. A nerve provides a common pathway for the Electrochemistry, electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called Nerve fascicle, fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. The entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are further classified as either Sensory neuron, sens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle
Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contraction, contract. Muscle tissue contains special Muscle contraction, contractile proteins called actin and myosin which interact to cause movement. Among many other muscle proteins, present are two regulatory proteins, troponin and tropomyosin. Muscle is formed during embryonic development, in a process known as myogenesis. Skeletal muscle tissue is striated consisting of elongated, multinucleate muscle cells called muscle fibers, and is responsible for movements of the body. Other tissues in skeletal muscle include tendons and perimysium. Smooth and cardiac muscle contract involuntarily, without conscious intervention. These muscle types may be activated both through the interaction of the central nervous system as well as by innervation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
