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Pirenzepine
Pirenzepine (Gastrozepin), an M1 selective antagonist, is used in the treatment of peptic ulcers, as it reduces gastric acid secretion and reduces muscle spasm. It is in a class of drugs known as muscarinic receptor antagonists - acetylcholine being the neurotransmitter of the parasympathetic nervous system which initiates the rest-and-digest state (as opposed to fight-or-flight), resulting in an increase in gastric motility and digestion; whereas pirenzepine would inhibit these actions and cause decreased gastric motility leading to delayed gastric emptying and constipation. It has no effects on the brain and spinal cord as it cannot diffuse through the blood–brain barrier. Pirenzepine has been investigated for use in myopia control. It promotes the homodimerization or oligomerisation of M1 receptors. See also * AFDX-384 * Telenzepine Telenzepine is a thienobenzodiazepine acting as selective M1 antimuscarinic. It is used in the treatment of peptic ulcers. Tel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myopia
Near-sightedness, also known as myopia and short-sightedness, is an eye disease where light focuses in front of, instead of on, the retina. As a result, distant objects appear blurry while close objects appear normal. Other symptoms may include headaches and eye strain. Severe near-sightedness is associated with an increased risk of retinal detachment, cataracts, and glaucoma. The underlying mechanism involves the length of the eyeball growing too long or less commonly the lens being too strong. It is a type of refractive error. Diagnosis is by eye examination. Tentative evidence indicates that the risk of near-sightedness can be decreased by having young children spend more time outside. This decrease in risk may be related to natural light exposure. Near-sightedness can be corrected with eyeglasses, contact lenses, or a refractive surgery. Eyeglasses are the easiest and safest method of correction. Contact lenses can provide a wider field of vision, but are associat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AFDX-384
AFDX-384 (BIBN-161) is a drug which acts as a selective antagonist of the muscarinic acetylcholine receptors, with selectivity for the M2 and M4 subtypes. It is used mainly for mapping the distribution of M2 and M4 muscarinic receptors in the brain, and studying their involvement in the development and treatment of dementia and schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social w .... See also * Pirenzepine (M1 selective antagonist) References {{Muscarinic acetylcholine receptor modulators Muscarinic antagonists Piperidines Ureas Benzodiazepines Pyridodiazepines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscarinic Antagonists
A muscarinic receptor antagonist (MRA) is a type of anticholinergic agent that blocks the activity of the muscarinic acetylcholine receptor. The muscarinic receptor is a protein involved in the transmission of signals through certain parts of the nervous system, and muscarinic receptor antagonists work to prevent this transmission from occurring. Notably, muscarinic antagonists reduce the activation of the parasympathetic nervous system. The normal function of the parasympathetic system is often summarised as "rest-and-digest", and includes slowing of the heart, an increased rate of digestion, narrowing of the airways, promotion of urination, and sexual arousal. Muscarinic antagonists counter this parasympathetic "rest-and-digest" response, and also work elsewhere in both the central and peripheral nervous systems. Drugs with muscarinic antagonist activity are widely used in medicine, in the treatment of low heart rate, overactive bladder, respiratory problems such as asthma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telenzepine
Telenzepine is a thienobenzodiazepine acting as selective M1 antimuscarinic. It is used in the treatment of peptic ulcers. Telenzepine is atropisomer Atropisomers are stereoisomers arising because of hindered rotation about a single bond, where energy differences due to steric strain or other contributors create a barrier to rotation that is high enough to allow for isolation of individual ...ic, in other words the molecule has a stereogenic C–N-axis. In neutral aqueous solution it displays a half-life for racemization of the order of 1000 years. The enantiomers have been resolved. The activity is related to the (+)-isomer which is about 500-fold more active than the (–)-isomer at muscarinic receptors in the rat cerebral cortex. See also * Pirenzepine References External links * Piperazines Muscarinic antagonists Carboxamides Lactams Thienobenzodiazepines {{gastrointestinal-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscarinic Acetylcholine Receptor M1
The muscarinic acetylcholine receptor M1, also known as the cholinergic receptor, muscarinic 1, is a muscarinic receptor that in humans is encoded by the ''CHRM1'' gene. It is localized to 11q13. This receptor is found mediating slow excitatory postsynaptic potential, EPSP at the ganglion in the postganglionic nerve, is common in exocrine glands and in the CNS. It is predominantly found bound to G proteins of class Gq alpha subunit, Gq that use upregulation of phospholipase C and, therefore, inositol trisphosphate and intracellular calcium as a signalling pathway. A receptor so bound would not be susceptible to Cholera toxin, CTX or Pertussis toxin, PTX. However, Gi (causing a downstream decrease in Cyclic adenosine monophosphate, cAMP) and Gs (causing an increase in cAMP) have also been shown to be involved in interactions in certain tissues, and so would be susceptible to PTX and CTX respectively. Effects *excitatory postsynaptic potential, EPSP in autonomic ganglia * Secret ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscarinic Receptor Antagonists
A muscarinic receptor antagonist (MRA) is a type of anticholinergic agent that blocks the activity of the muscarinic acetylcholine receptor. The muscarinic receptor is a protein involved in the transmission of signals through certain parts of the nervous system, and muscarinic receptor antagonists work to prevent this transmission from occurring. Notably, muscarinic antagonists reduce the activation of the parasympathetic nervous system. The normal function of the parasympathetic system is often summarised as "rest-and-digest", and includes slowing of the heart, an increased rate of digestion, narrowing of the airways, promotion of urination, and sexual arousal. Muscarinic antagonists counter this parasympathetic "rest-and-digest" response, and also work elsewhere in both the central and peripheral nervous systems. Drugs with muscarinic antagonist activity are widely used in medicine, in the treatment of low heart rate, overactive bladder, respiratory problems such as asthma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholine
Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Parts in the body that use or are affected by acetylcholine are referred to as cholinergic. Substances that increase or decrease the overall activity of the cholinergic system are called cholinergics and anticholinergics, respectively. Acetylcholine is the neurotransmitter used at the neuromuscular junction—in other words, it is the chemical that motor neurons of the nervous system release in order to activate muscles. This property means that drugs that affect cholinergic systems can have very dangerous effects ranging from paralysis to convulsions. Acetylcholine is also a neurotransmitter in the autonomic nervous system, both as an internal transmitter for the sympathetic nervous system and as the final product released by the par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasympathetic Nervous System
The parasympathetic nervous system (PSNS) is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of the autonomic nervous system, and sometimes considered an independent system. The autonomic nervous system is responsible for regulating the body's unconscious actions. The parasympathetic system is responsible for stimulation of "rest-and-digest" or "feed and breed" activities that occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion, and defecation. Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response. Nerve fibres of the parasympathetic nervous system arise from the central nervous system. Specific nerves include sev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood–brain Barrier
The blood–brain barrier (BBB) is a highly selective semipermeable border of endothelial cells that prevents solutes in the circulating blood from ''non-selectively'' crossing into the extracellular fluid of the central nervous system where neurons reside. The blood–brain barrier is formed by endothelial cells of the capillary wall, astrocyte end-feet ensheathing the capillary, and pericytes embedded in the capillary basement membrane. This system allows the passage of some small molecules by passive diffusion, as well as the selective and active transport of various nutrients, ions, organic anions, and macromolecules such as glucose and amino acids that are crucial to neural function. The blood–brain barrier restricts the passage of pathogens, the diffusion of solutes in the blood, and large or hydrophilic molecules into the cerebrospinal fluid, while allowing the diffusion of hydrophobic molecules (O2, CO2, hormones) and small non-polar molecules. Cells of the barrier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptic Ulcers
Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines is a duodenal ulcer. The most common symptoms of a duodenal ulcer are waking at night with upper abdominal pain and upper abdominal pain that improves with eating. With a gastric ulcer, the pain may worsen with eating. The pain is often described as a burning or dull ache. Other symptoms include belching, vomiting, weight loss, or poor appetite. About a third of older people have no symptoms. Complications may include bleeding, perforation, and blockage of the stomach. Bleeding occurs in as many as 15% of cases. Common causes include the bacteria ''Helicobacter pylori'' and non-steroidal anti-inflammatory drugs (NSAIDs). Other, less common causes include tobacco smoking, stress as a result of other serious health conditions, Behçet's d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPCR Oligomer
A GPCR oligomer is a protein complex that consists of a small number ( ''oligoi'' "a few", ''méros'' "part, piece, component") of G protein-coupled receptors (GPCRs). It is held together by covalent bonds or by intermolecular forces. The subunits within this complex are called protomers, while unconnected receptors are called monomers. Receptor homomers consist of identical protomers, while heteromers consist of different protomers. Receptor homodimers – which consist of two identical GPCRs – are the simplest homomeric GPCR oligomers. Receptor heterodimers – which consist of two different GPCRs – are the simplest heteromeric GPCR oligomers. The existence of receptor oligomers is a general phenomenon, whose discovery has superseded the prevailing paradigmatic concept of the function of receptors as plain monomers, and has far-reaching implications for the understanding of neurobiological diseases as well as for the development of drugs. Discovery For a long time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Spasm
A spasm is a sudden involuntary contraction of a muscle, a group of muscles, or a hollow organ such as the bladder. A spasmodic muscle contraction may be caused by many medical conditions, including dystonia. Most commonly, it is a muscle cramp which is accompanied by a sudden burst of pain. A muscle cramp is usually harmless and ceases after a few minutes. It is typically caused by ion imbalance or muscle overload. There are other causes of involuntary muscle contractions, and some of these may cause a health problem. Description and causes Various kinds of involuntary muscle activity may be referred to as a "spasm". A spasm may be a muscle contraction caused by abnormal nerve stimulation or by abnormal activity of the muscle itself. A spasm may lead to muscle strains or tears in tendons and ligaments if the force of the spasm exceeds the tensile strength of the underlying connective tissue. This can occur with a particularly strong spasm or with weakened connecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
