serotonin (sĕr'ətō`nĭn), organic compound that was first recognized as a powerful vasoconstrictor occurring in blood serum. It was partially purified, crystallized, and named in 1948, and its structure was deduced a year later. Independent work indicated that serotonin was widely distributed in nature and occurred in tissues other than blood. It has been shown to be in many representatives of the animal kingdom, in wasp stings and scorpion venom, in various fruits, such as pineapples, bananas, and plums, and in various nuts. It has been estimated that an adult human contains about 5 to 10 mg of serotonin, 90% of which is in the intestine and the rest in blood platelets and the brain. One role of the compound is as a neurotransmitter (see acetylcholine acetylcholine , a small organic molecule liberated at nerve endings as a neurotransmitter. It is particularly important in the stimulation of muscle tissue. The transmission of an impulse to the end of the nerve causes it to release neurotransmitter molecules onto
..... Click the link for more information. ) whose participation is being sought in diverse functions including learning, sleep, and control of mood. The structural similarity of serotonin to several drugs known to cause mental aberrations, such as LSD LSD or lysergic acid diethylamide , alkaloid synthesized from lysergic acid, which is found in the fungus ergot (Claviceps purpurea).
..... Click the link for more information. , has prompted much speculation as to the role of serotonin in naturally occurring mental disorders such as schizophrenia or depression. The function of serotonin in blood platelets is not clear; it seems to have no important role in the clotting mechanism. Its function in stings and venoms might be that of an irritant, since intravenous injections of serotonin in man produce pain at the site of injection, gasping, coughing, a general tingling and prickling sensation, nausea, cramps, and other unpleasant symptoms.

serotonin

Chemical (5-hydroxytryptamine, or 5-HT) derived from the amino acid tryptophan. It occurs in brain and intestinal tissue, platelets, and certain connective-tissue cells and is a component of many animal venoms (e.g., wasp, toad). A strong stimulator of blood-vessel constriction and a neurotransmitter, serotonin concentrates in certain brain areas, especially the midbrain and hypothalamus. Some cases of depression are apparently caused by reduced amounts or activity of serotonin in the brain; many antidepressants counteract that condition. Excessive brain serotonin activity may cause migraine headaches and nausea. LSD may act by inhibiting the action of serotonin.

serotonin [‚sir·ə′tō·nən]

(biochemistry)

C₁₀H₁₂ON₂A compound derived from tryptophan which functions as a local vasoconstrictor, plays a role in neurotransmission, and has pharmacologic properties. Also known as 5-hydroxytryptamine.

Serotonin

A compound, also known as 5-hydroxytryptamine (5-HT), derived from tryptophan, an indole-containing amino acid. It is widely distributed in the animal and vegetable kingdoms. In mammals it is found in gastrointestinal enterochromaffin cells, in blood platelets, and in brain and nerve tissue. Serotonin is a local vasoconstrictor, plays a role in brain and nerve function and in regulation of gastric secretion and intestinal peristalsis, and has pharmacologic properties. It is inactivated by monoamine oxidases (MAO-A and -B), enzymes that also inactivate other neurotransmitters such as norepinephrine and dopamine.

Serotonin is concentrated in certain areas of the brain; the hypothalamus and midbrain contain large amounts, while the cortex and cerebellum contain low concentrations. Like most neurotransmitters, it is stored in granules inside nerve endings, and is thus not exposed to inactivation by monoamine oxidases until it is released into the synaptic space between nerves. When a serotonin-containing nerve fires, serotonin is released and can bind to any one of a series of at least 14 distinct downstream serotonin receptors (5-HT receptors). Release of serotonin or other stored neurotransmitters can also be induced by alkaloids such as reserpine, which have been used as tranquilizing agents in the treatment of nervous and mental disorders. Although pharmacologic doses of serotonin produce a type of sedation and other depressant conditions of the nervous system, several types of clinically useful antidepressants, such as monoamine oxidase (MAO) inhibitors, tricyclic antidepressants, and selective serotonin reuptake inhibitors (SSRIs), act by increasing the amount of active serotonin in nerve synapses in particular brain regions. Conversely, various conditions that lower serotonin levels are associated with depression, suggesting that normal to slightly elevated serotonin levels tend to elevate mood and prevent depression. See Affective disorders, Brain, Nervous system (vertebrate), Neurosecretion, Psychopharmacology

Serotonin

(also 5-hydroxytryptamine), a biologically active substance in human and animal blood and tissue that in several cases has proved to be a mediator of the nervous system, both on the periphery and in nerve centers (mainly, in the hypothalamus). Serotonin’s chemical structure is

Serotonin was first isolated and obtained in crystalline form from bovine serum in 1947. It has been found in all animal groups studied. It is present in large amounts in the poisons of coelenterates, mollusks, arthropods, and amphibians; it is also found in plants. In the body, serotonin is synthesized from the amino acid tryptophan; in humans and most vertebrates, serotonin synthesis is conducted mainly in the cells of the mucosal membrane of the small intestine, as well as in the pancreas and central nervous system. In tissues, serotonin is converted into 5-hydroxyindoleacetic acid, which is eliminated from the body by the kidneys. The enzyme monoamine oxidase is very important in the metabolism of serotonin.

Serotonin has a great influence on vascular tone and participates in the humoral regulation of the functions of the digestive, excretory, endocrine, and central nervous systems. Blood (primarily thrombocytes) contains 0.02 to 0.6 mg/liter of serotonin. The action of hallucinogens, including LSD and mescaline, is explained by disorders of serotonin metabolism and action in the central nervous system. It is believed that serotonin metabolism disorders may cause a variety of pathological conditions, including myocardial infarction, ulcers, and several men-taldiseases.

G. N. KASSIL’

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No references found			The overall use of antidepressants and the use of selective serotonin reuptake inhibitors increased sharply from 1996 to 2004, when both trends plateaued. Antidepressants in pregnancy by Perspectives on Sexual and Reproductive Health Patients with depression who take tricyclic antidepressants and selective serotonin reuptake inhibitors concurrently have almost twice the risk of developing type 2 diabetes as those taking tricyclic medications alone, Lauren C. TCA/SSRI treatment can lead to diabetes by Sullivan, Michelle / Clinical Psychiatry News Psychiatry, neurology, pediatrics, and other medical professionals from the US and UK who have conducted studies on these treatments discuss the use of medications, including selective serotonin reuptake inhibitors and antidepressants, anticonvulsants and mood stabilizers, antipsychotics, cholinesterase inhibitors, and stimulants and nonstimulants for attention and hyperactivity. Clinical manual for the treatment of autism by SciTech Book News			selective filling selective flotation selective forgetting selective fracturing selective fusion selective heating selective identification feature selective inhibition selective interference selective jamming selective laser sintering selective loading selective medium Selective Mining selective permeability selective photoelectric effect selective plating selective poisoning selective polymerization selective quenching selective radiator selective reflection selective replacement selective ringing selective scattering Selective serotonin reuptake inhibitors selective service selective solubility diffusion selective solvent Selective Telephone Communications selective trace selective transmission selectively doped heterojunction transistor selectivity selectivity coefficient selectivity diagram Selectivity of a Radio Receiver Selector selector channel selector pen selector switch Selector, Electromechanical Selectric typewriter Selemdzha Selenduma Selene Selenga Selenga River Selenginsk selenic acid Selenide			selective reflection Selective reject selective release selective release process Selective Repeat Automatic Repeat Request selective replacement Selective Reserve Unit Selective Retention Indicator Selective Retrograde Arterialization of the Coronary Vein Selective Ringing Selective Ringing Selective Routing Data Base Selective Saturation Recovery with Gradient Refocusing Selective Scanning selective scattering Selective Semisolid Brucella Medium Selective Sentinel Lymph Node Dissection Selective Sequence Electronic Calculator Selective seratonin re-uptake inhibitor Selective seratonin re-uptake inhibitor Selective Serotonin Inhibitors Selective serotonin re-uptake inhibitor Selective serotonin re-uptake inhibitor Selective serotonin reuptake enhancer selective serotonin reuptake inhibitor selective serotonin reuptake inhibitor selective serotonin reuptake inhibitor selective serotonin reuptake inhibitor selective serotonin reuptake inhibitor Selective Serotonin Reuptake Inhibitor Antidepressant Selective serotonin reuptake inhibitors selective serotonin reuptake inhibitors (SSRIs) selective serotonin reuptake inhibitors (SSRIs) selective serotonin reuptake inhibitors (SSRIs) Selective serotonin uptake inhibitors Selective Serotonin-Noradrenalin Reuptake Inhibitor selective service selective service selective service selective service Selective Service Administration Selective Service Registration Selective Service System Selective Service System Selective Service System Selective Service System Selective Signaling selective slaughter selective slaughter selective slaughter selective slaughter selective solubility diffusion selective solvent selective stain selective synchronization Selective Tape Print Selective Telephone Communications selective termination of pregnancy Selective Tidal Stream Transport Selective Time Division Multiple Access Selective Tissue Estrogenic Activity Regulator

Serotonin (redirected from Selective serotonin reuptake inhibitors)

serotonin

Serotonin
(redirected from Selective serotonin reuptake inhibitors)