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RAC 421-II
RAC 421-II, also referred to simply as RAC 421, is a quaternary local anesthetic that acts through intracellular blockage of the NaKATPase channel. Function As a quaternary ammonium analogue of another local anesthetic, RAC 109, RAC 421-II is permanently charged and so cannot cross the hydrophobic phospholipid cell membrane. As it cannot diffuse across the cell membrane, it cannot exert its inhibitory effects on the intracellular surface of NaKATPase. As such, it can only exert its anesthetic properties if it is injected into the cytosol of the nerve fibre. Inhibition occurs through allowing the sodium and potassium gradients across the cell membrane to dissipate. NaKATPase blockage preferentially inhibits firing of nociceptive nerve fibres due to their relatively low cell diameter and so low tolerance to NaKATPase inhibitors. This is in contrast to non-quaternary anesthetics like benzocaine and tetracaine Tetracaine, also known as amethocaine, is an ester local anesthet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloride
In chemistry, a hydrochloride is an acid salt resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base (e.g. an amine). An alternative name is chlorhydrate, which comes from French. An archaic alternative name is muriate, derived from hydrochloric acid's ancient name: muriatic acid. Uses Converting amines into their hydrochlorides is a common way to improve their water solubility, which can be desirable for substances used in medications. The European Pharmacopoeia lists more than 200 hydrochlorides as active ingredients in medications. These hydrochlorides, compared to free bases, may more readily dissolve in the gastrointestinal tract and be absorbed into the bloodstream more quickly. Additionally, many hydrochlorides of amines have a longer shelf-life than their respective free bases. Amine hydrochlorides represent latent forms of a more reactive free base. In this regard, formation of an amine hydrochloride confers protection. This eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytosol
The cytosol, also known as cytoplasmic matrix or groundplasm, is one of the liquids found inside cells (intracellular fluid (ICF)). It is separated into compartments by membranes. For example, the mitochondrial matrix separates the mitochondrion into many compartments. In the eukaryotic cell, the cytosol is surrounded by the cell membrane and is part of the cytoplasm, which also comprises the mitochondria, plastids, and other organelles (but not their internal fluids and structures); the cell nucleus is separate. The cytosol is thus a liquid matrix around the organelles. In prokaryotes, most of the chemical reactions of metabolism take place in the cytosol, while a few take place in membranes or in the periplasmic space. In eukaryotes, while many metabolic pathways still occur in the cytosol, others take place within organelles. The cytosol is a complex mixture of substances dissolved in water. Although water forms the large majority of the cytosol, its structure and prope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Local Anesthetics
A local anesthetic (LA) is a medication that causes absence of pain sensation. In the context of surgery, a local anesthetic creates an absence of pain in a specific location of the body without a loss of consciousness, as opposed to a general anesthetic. When it is used on specific nerve pathways (local anesthetic nerve block), paralysis (loss of muscle power) also can be achieved. Examples Short Duration & Low Potency Procaine Chloroprocaine Medium Duration & Potency Lidocaine Prilocaine High Duration & Potency Tetracaine Bupivacaine Cinchocaine Ropivacaine Clinical LAs belong to one of two classes: aminoamide and aminoester local anesthetics. Synthetic LAs are structurally related to cocaine. They differ from cocaine mainly in that they have a very low abuse potential and do not produce hypertension or (with few exceptions) vasoconstriction. They are used in various techniques of local anesthesia such as: * Topical anesthesia (surface) * Topical administration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetracaine
Tetracaine, also known as amethocaine, is an ester local anesthetic used to numb the eyes, nose, or throat. It may also be applied to the skin before starting an intravenous (injection) to decrease pain from the procedure. Typically it is applied as a liquid to the area. Onset of effects when used in the eyes is within 30 seconds and last for less than 15 minutes. Common side effects include a brief period of burning at the site of use. Allergic reactions may uncommonly occur. Long-term use is generally not recommended as it may slow healing of the eye. It is unclear if use during pregnancy is safe for the baby. Tetracaine is in the ester-type local anesthetic family of medications. It works by blocking the sending of nerve impulses. Tetracaine was patented in 1930 and came into medical use in 1941. It is on the World Health Organization's List of Essential Medicines Medical uses A systematic review investigated tetracaine for use in emergency departments, especially for star ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzocaine
Benzocaine, sold under the brand name Orajel amongst others, is an ester local anesthetic commonly used as a topical pain reliever or in cough drops. It is the active ingredient in many over-the-counter anesthetic ointments such as products for oral ulcers. It is also combined with antipyrine to form A/B otic drops to relieve ear pain and remove earwax. In the US, products containing benzocaine for oral application are contraindicated in children younger than two years old. In the European Union, the contraindication applies to children under 12 years of age. It was first synthesised in 1890 in Germany and approved for medical use in 1902. Medical uses Benzocaine is indicated to treat a variety of pain-related conditions. It may be used for: * Local anesthesia of oral and pharyngeal mucous membranes (sore throat, cold sores, mouth ulcers, toothache, sore gums, denture irritation)AHFS Drug Information 2007. McEvoy GK, ed. Benzocaine. Bethesda, MD: American Society of Healt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nociception
Nociception (also nocioception, from Latin ''nocere'' 'to harm or hurt') is the sensory nervous system's process of encoding noxious stimuli. It deals with a series of events and processes required for an organism to receive a painful stimulus, convert it to a molecular signal, and recognize and characterize the signal in order to trigger an appropriate defense response. In nociception, intense chemical (e.g., capsaicin present in Chili pepper or Cayenne pepper), mechanical (e.g., cutting, crushing), or thermal (heat and cold) stimulation of sensory neurons called nociceptors produces a signal that travels along a chain of nerve fibers via the spinal cord to the brain. Nociception triggers a variety of physiological and behavioral responses to protect the organism against an aggression and usually results in a subjective experience, or perception, of pain in sentient beings. Detection of noxious stimuli Potentially damaging mechanical, thermal, and chemical stimuli are detected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature, and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Among many other useful sodium compounds, sodium hydroxide (lye) is used in soap manufacture, and sodium chloride (edible salt) is a de-icing agent and a nutrient for animals including h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the 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, within the nerve, is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Within a nerve, each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. Finally, the entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffusion
Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical potential. It is possible to diffuse "uphill" from a region of lower concentration to a region of higher concentration, like in spinodal decomposition. The concept of diffusion is widely used in many fields, including physics (particle diffusion), chemistry, biology, sociology, economics, and finance (diffusion of people, ideas, and price values). The central idea of diffusion, however, is common to all of these: a substance or collection undergoing diffusion spreads out from a point or location at which there is a higher concentration of that substance or collection. A gradient is the change in the value of a quantity, for example, concentration, pressure, or temperature with the change in another variable, usually distance. A change in c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Compound
In chemistry, a quaternary compound is a compound consisting of exactly four chemical elements. In another use of the term in organic chemistry, a quaternary compound is or has a cation consisting of a central positively charged atom with four substituents, especially organic (alkyl and aryl) groups, discounting hydrogen atoms. The best-known quaternary compounds are quaternary ammonium salts, having a nitrogen atom at the centre. For example, in the following reaction, the nitrogen atom is said to be quaternized as it has gone from 3 to 4 substituents: :R3N + RCl -> R4N+Cl- Other examples include substituted phosphonium salts (), substituted arsonium salts () like arsenobetaine, as well as some arsenic-containing superconductors. Substituted stibonium () and bismuthonium salts () have also been described. See also *Binary compound *Ternary compound *Onium ion *Quaternary phase In materials chemistry, a quaternary phase is a chemical compound containing four element ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
