5-Hydroxytryptamine distribution

Martin, G.R. (1994) Vascular receptors for 5-hydroxytryptamine distribution, function and classification. Pharmacol. Then, 62, 283-324. 

Bonaventure, P., Nepomuceno, D., Kwok, A. et al. Reconsideration of 5-hydroxytryptamine (5-HT)7 receptor distribution using [3H]5-carboxamidotryptamine and [3H]8-hydroxy-2-(di-n-propylamino)tatraline Analysis in brain of 5-HT 1A knock-out and 5-HT1A,1B double knock-out mice. /. Pharmacol. Exp. Ther. 302 240-248, 2002. 

Kirby LG, Chou-Green JM, Davis K, Lucki I (1997) The effects of different stressors on extracellular 5-hydroxytryptamine and 5-hydroxyindoleacetic acid. Brain Res 760 218-230 Kirby LG, Rice KC, Valentino RJ (2000) Effects of corticotropin-releasing factor on neuronal activity in the serotonergic dorsal raphe nucleus. Neuropsychopharmacology 22 148-162 Kozicz T, Yanaihara H, Arimura A (1998) Distribution of urocortin-like immunoreactivity in the central nervous system of the rat. J Comp Neurol 391 1-10 Lavicky J, Dunn AJ (1993) Corticotropin-releasing factor stimulates catecholamine release in hypothalamus and prefrontal cortex in freely moving rats as assessedby microdialysis. J Neurochem 60 602-612... 

Serotonin, or 5-hydroxytryptamine (5-HT), is a monoamine widely distributed in many cells of the body, with about l%-2% of its entire body content present in the CNS. 

The neurotransmitter serotonin (5-hydroxytryptamine [5-HT]) is widely distributed in the CNS, subsuming a variety of functions including drive satiety, mood, aggression, anxiety, and compulsive and impulsive behaviors. It may be an important neurotransmitter in psychiatric symptoms commonly associated with PTSD such as aggression, obsessive/intrusive thoughts, alcohol and substance abuse, and suicidal behavior (Friedman, 1990). Suicidal behavior is known to be associated with both childhood maltreatment and low 5-HT functioning (Van der Kolk et ah, 1991 Benkelfat,... 

Hydroxytryptamine is widely distributed in plant and animal tissues, mast cells, platelets, the enterochromaffin cells located throughout the gastrointestinal tract, and in certain regions of the brain. It is also present in the venoms and stings. Some fruits such as bananas, pineapples, tomatoes and plums contain considerable amount of 5-HT. 

Serotonin and melatonin. The indolealkyl amine serotonin (5-hydroxytryptamine, 5-HT Fig. 30-28), is found in all mammalian brains and in invertebrates as well. Its distribution in the brain is limited, serotonin-containing neurons being found in the raphe nuclei of the brainstem from which they ascend into the brain and down the spinal cord. Serotonin-containing neurons have been traced within brains of snails using 3H-labeled serotonin.777 Studies with these simpler brains have revealed both inhibitory and excitatory responses to these neurons. Serotonin-accumulating neurons are also found in the retina778 and are widely distributed in the peripheral nervous... 

Tryptamine and its Al-methyl and A/Al-dimethyl derivatives (Figure 6.70) are widely distributed in plants, as are simple hydroxylated derivatives such as 5-hydroxytryptamine (serotonin). These are formed (Figure 6.70) by a series of decarboxylation, methylation, and hydroxylation reactions, though the sequences of these reactions are found to vary according to final product and/or... 

Hirst WD, Abrahamsen B, Blaney FE, et al. Differences in the central nervous system distribution and pharmacology of the mouse 5-hydroxytryptamine-6 receptor compared with rat and human receptors investigated by radioligand binding, site-directed mutagenesis, and molecular modeling. Mol Pharmacol 2003 64 1295-1308. 

Serotonin or 5-hydroxytryptamine (5-HT) receptors with 7 subtypes and at least 15 distinct members mediate a diverse array of physiological functions both in the central nervous system and in the periphery (1). Their varied cellular distribution and complex signal transduction in part account... 

Key Words 5-Hydroxytryptamine immunocytochemistry anatomical distribution cellular and subcellular localization internalization colocalization. 

The first of at least 14 serotonin (5-hydroxytryptamine [5-HT]) receptor types currently known to exist in the mammalian central nervous system (CNS) was pharmacologically defined more than 25 yr ago (1,2). Yet, it is only within the last 15 yr, with the cloning and sequencing of these receptors, that it has become possible to visualize their distribution at cellular and subcellular... 

Reynolds GP, Mason SL, Meldrum A, et al. 5-Hydroxytryptamine (5-HT)4 receptors in post mortem human brain tissue distribution, pharmacology and effects of neurodegenerative diseases. Brit J Pharmacol 1995 114 993-998. 

Since they are tryptamine derivatives, the indolic hallucinogens are structurally related to the neurohumoral factor serotonin (5-hydroxytryptamine). Serotonin is widely distributed in warmblooded animals. It accumulates in the brain, where it plays a role in the biochemistry of nervous regulations. Consequently, it seems that certain tryptamine structures which occur so frequently in hallucinogens, as well as in the neurohormone serotonin, may be biochemically important in the metabolism of psychic functions. . . ... 

Serotonin or 5-hydroxytryptamine (5-HT), a monoamine, is widely distributed in many cells of the body and about 1-2% of the entire serotonin body content is found in the CNS. Serotonin is synthesized by the enzyme amino acid decarboxylase from 5-hydroxytryptophan (which is derived from tryptophan via tryptophan hydroxylase). The rate-limiting step is the production of 5-hydroxytryptophan by tryptophan hydroxylase. Serotonin is removed from the synapse by a high-affinity serotonin uptake site that is capable of transporting serotonin in either direction, depending on the concentration. 

As well as the microsomal enzymes involved in the oxidation of amines, there are a number of other amine oxidase enzymes which have a different subcellular distribution. The most important are the monoamine oxidases and the diamine oxidases. The monoamine oxidases are located in the mitochondria within the cell and are found in the liver and also other organs such as the heart and central nervous system and in vascular tissue. They are a group of flavoprotein enzymes with overlapping substrate specificities. Although primarily of importance in the metabolism of endogenous compounds such as 5-hydroxytryptamine they may be involved in the metabolism of foreign compounds. The enzyme found in the liver will deaminate secondary and tertiary aliphatic amines as well as primary amines, although the latter are the preferred substrates... 

Serotonin, or 5-hydroxytryptamine (5-HT), is another monoamine whose important central effects have only been recognized recently. It had previously been known as a vasoconstrictor in the plasma. Once identified chemically, it was found to be widely distributed in the body. After determination of significant brain levels in the hypothalamus, medulla, midbrain, and other areas (Table 12-3), and after establishing its biosynthetic paths, serotonin became recognized as a neurotransmitter. 5-HT is presently less well understood than are the catecholamines. Figure 12-3 outlines its biosynthesis from the essential amino acid tryptophan. Try enters the brain by active transport (as is L-dopa) and is hydroxylated there by tryptophan hydroxylase, which is an enzyme similar to if not identical to, tyrosine hydroxylase. 

Indomethacin is a potent anti-inflammatory and anti-pyretic compound. Given orally, it inhibits the formation of the cotton-pellet granuloma in the rat, being about 85 times more potent than phenylbutazone, and equally active in both intact and adrenalectomized rats. It inhibits oedema of the rat-foot, produced by either carrageenan or mustard, but does not inhibit that produced by egg-white, formalin, yeast or 5-hydroxytryptamine. As an antipyretic, it is 10-20 times more powerful than phenylbutazone. Indomethacin is well absorbed in all species, but there is considerable variation in its distribution and metabolism. Man tolerates the drug better than do other species, and is less liable to the gastro-intestinal irritation encountered in experimental animals . ... 

As long ago as the middle of the nineteenth century, physiologists were aware that blood serum contained a vasoconstrictor substance, but this material ( vasotonin or serotonin ) was not isolated in a pure form until 1948 . Rapport shortly afterwards identified serotonin as 5-hydroxytryptamine . A few years later Erspamer demonstrated that enteramine , an active material he had detected in extracts of intestinal mucosa almost 20 years earlier, was also 5-hydroxytryptamine . Subsequently, 5-hydroxytryptamine was found to be widely distributed in tissues and to possess a... 

An explanation of the mode of action of the monoamine oxidase inhibitors in terms of their intervention in central transmission processes is difficult for several reasons. Monoamine oxidase is widely distributed in the body and some of the consequences of its inhibition may arise peripherally in the brain the enzyme participates in the inactivation of at least three substances (noradrenaline, dopamine and 5-hydroxytryptamine). Not all monoamine oxidase inhibitors have antidepressant activity but those that have may owe at least part of their activity to an action other than enzyme inhibition. 

Cho, C. H. and Mettrick, D. F. (1982) Circadian variation in the distribution of Hymenolepsis diminuta (Cestoda) and 5-hydroxytryptamine levels in the gastro-intestinal tract of the laboratory rat. Parasitology 84 431-441. 

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