Serotonin
A biochemical messenger and regulator, synthesized from the essential amino acid L-TRYPTOPHAN. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Multiple receptor families (RECEPTORS, SEROTONIN) explain the broad physiological actions and distribution of this biochemical mediator.
Serotonin Plasma Membrane Transport Proteins
Sodium chloride-dependent neurotransmitter symporters located primarily on the PLASMA MEMBRANE of serotonergic neurons. They are different than SEROTONIN RECEPTORS, which signal cellular responses to SEROTONIN. They remove SEROTONIN from the EXTRACELLULAR SPACE by high affinity reuptake into PRESYNAPTIC TERMINALS. Regulates signal amplitude and duration at serotonergic synapses and is the site of action of the SEROTONIN UPTAKE INHIBITORS.
Receptors, Serotonin
Receptor, Serotonin, 5-HT2A
A serotonin receptor subtype found widely distributed in peripheral tissues where it mediates the contractile responses of variety of tissues that contain SMOOTH MUSCLE. Selective 5-HT2A receptor antagonists include KETANSERIN. The 5-HT2A subtype is also located in BASAL GANGLIA and CEREBRAL CORTEX of the BRAIN where it mediates the effects of HALLUCINOGENS such as LSD.
Receptor, Serotonin, 5-HT1A
A serotonin receptor subtype found distributed through the CENTRAL NERVOUS SYSTEM where they are involved in neuroendocrine regulation of ACTH secretion. The fact that this serotonin receptor subtype is particularly sensitive to SEROTONIN RECEPTOR AGONISTS such as BUSPIRONE suggests its role in the modulation of ANXIETY and DEPRESSION.
Serotonin Uptake Inhibitors
Serotonin Antagonists
Drugs that bind to but do not activate serotonin receptors, thereby blocking the actions of serotonin or SEROTONIN RECEPTOR AGONISTS.
Receptor, Serotonin, 5-HT2C
A serotonin receptor subtype found primarily in the CENTRAL NERVOUS SYSTEM and the CHOROID PLEXUS. This receptor subtype is believed to mediate the anorectic action of SEROTONIN, while selective antagonists of the 5-HT2C receptor appear to induce ANXIETY. Several isoforms of this receptor subtype exist, due to adenine deaminase editing of the receptor mRNA.
Receptor, Serotonin, 5-HT2B
Receptors, Serotonin, 5-HT2
A subclass of G-protein coupled SEROTONIN receptors that couple preferentially to the GQ-G11 G-PROTEINS resulting in increased intracellular levels of INOSITOL PHOSPHATES and free CALCIUM.
Serotonin Agents
Drugs used for their effects on serotonergic systems. Among these are drugs that affect serotonin receptors, the life cycle of serotonin, and the survival of serotonergic neurons.
Receptor, Serotonin, 5-HT1B
A serotonin receptor subtype found at high levels in the BASAL GANGLIA and the frontal cortex. It plays a role as a terminal autoreceptor that regulates the rate of SEROTONIN release from nerve endings. This serotonin receptor subtype is closely related to and has similar drug binding properties as the 5-HT1D RECEPTOR. It is particularly sensitive to the agonist SUMATRIPTAN and may be involved in mediating the drug's antimigraine effect.
Serotonin Receptor Agonists
Endogenous compounds and drugs that bind to and activate SEROTONIN RECEPTORS. Many serotonin receptor agonists are used as ANTIDEPRESSANTS; ANXIOLYTICS; and in the treatment of MIGRAINE DISORDERS.
Receptors, Serotonin, 5-HT1
A subclass of G-protein coupled SEROTONIN receptors that couple preferentially to GI-GO G-PROTEINS resulting in decreased intracellular CYCLIC AMP levels.
Serotonin Syndrome
An adverse drug interaction characterized by altered mental status, autonomic dysfunction, and neuromuscular abnormalities. It is most frequently caused by use of both serotonin reuptake inhibitors and monoamine oxidase inhibitors, leading to excess serotonin availability in the CNS at the serotonin 1A receptor.
Serotonin 5-HT2 Receptor Antagonists
Drugs that bind to but do not activate SEROTONIN 5-HT2 RECEPTORS, thereby blocking the actions of SEROTONIN or SEROTONIN 5-HT2 RECEPTOR AGONISTS. Included under this heading are antagonists for one or more specific 5-HT2 receptor subtypes.
Receptors, Serotonin, 5-HT3
A subclass of serotonin receptors that form cation channels and mediate signal transduction by depolarizing the cell membrane. The cation channels are formed from 5 receptor subunits. When stimulated the receptors allow the selective passage of SODIUM; POTASSIUM; and CALCIUM.
Serotonin 5-HT2 Receptor Agonists
Endogenous compounds and drugs that specifically stimulate SEROTONIN 5-HT2 RECEPTORS. Included under this heading are agonists for one or more of the specific 5-HT2 receptor subtypes.
Tryptophan Hydroxylase
An enzyme that catalyzes the hydroxylation of TRYPTOPHAN to 5-HYDROXYTRYPTOPHAN in the presence of NADPH and molecular oxygen. It is important in the biosynthesis of SEROTONIN.
Serotonin 5-HT1 Receptor Agonists
Endogenous compounds and drugs that specifically stimulate SEROTONIN 5-HT1 RECEPTORS. Included under this heading are agonists for one or more of the specific 5-HT1 receptor subtypes.
Receptors, Serotonin, 5-HT4
A subtype of G-protein-coupled SEROTONIN receptors that preferentially couple to GS STIMULATORY G-PROTEINS resulting in increased intracellular CYCLIC AMP. Several isoforms of the receptor exist due to ALTERNATIVE SPLICING of its mRNA.
Serotonin 5-HT1 Receptor Antagonists
Drugs that bind to but do not activate SEROTONIN 5-HT1 RECEPTORS, thereby blocking the actions of SEROTONIN 5-HT1 RECEPTOR AGONISTS. Included under this heading are antagonists for one or more of the specific 5-HT1 receptor subtypes.
Hydroxyindoleacetic Acid
Hydroxyindoleacetic acid (5HIAA) is a major metabolite of serotonin, a neurotransmitter, formed by the action of monoamine oxidase and aldehyde dehydrogenase, and its measurement in urine is often used as a biomarker for serotonin synthesis in clinical and research settings.
Fluoxetine
The first highly specific serotonin uptake inhibitor. It is used as an antidepressant and often has a more acceptable side-effects profile than traditional antidepressants.
Citalopram
A furancarbonitrile that is one of the SEROTONIN UPTAKE INHIBITORS used as an antidepressant. The drug is also effective in reducing ethanol uptake in alcoholics and is used in depressed patients who also suffer from tardive dyskinesia in preference to tricyclic antidepressants, which aggravate this condition.
Serotonergic Neurons
Neurons whose primary neurotransmitter is SEROTONIN.
Ketanserin
A selective serotonin receptor antagonist with weak adrenergic receptor blocking properties. The drug is effective in lowering blood pressure in essential hypertension. It also inhibits platelet aggregation. It is well tolerated and is particularly effective in older patients.
5-Hydroxytryptophan
The immediate precursor in the biosynthesis of SEROTONIN from tryptophan. It is used as an antiepileptic and antidepressant.
Raphe Nuclei
Collections of small neurons centrally scattered among many fibers from the level of the TROCHLEAR NUCLEUS in the midbrain to the hypoglossal area in the MEDULLA OBLONGATA.
Paroxetine
8-Hydroxy-2-(di-n-propylamino)tetralin
Methysergide
An ergot derivative that is a congener of LYSERGIC ACID DIETHYLAMIDE. It antagonizes the effects of serotonin in blood vessels and gastrointestinal smooth muscle, but has few of the properties of other ergot alkaloids. Methysergide is used prophylactically in migraine and other vascular headaches and to antagonize serotonin in the carcinoid syndrome.
Fenclonine
A selective and irreversible inhibitor of tryptophan hydroxylase, a rate-limiting enzyme in the biosynthesis of serotonin (5-HYDROXYTRYPTAMINE). Fenclonine acts pharmacologically to deplete endogenous levels of serotonin.
Receptor, Serotonin, 5-HT1D
A serotonin receptor subtype that is localized to the CAUDATE NUCLEUS; PUTAMEN; the NUCLEUS ACCUMBENS; the HIPPOCAMPUS, and the RAPHE NUCLEI. It plays a role as a terminal autoreceptor that regulates the rate of SEROTONIN release from nerve endings. This serotonin receptor subtype is closely related to and has similar drug binding properties as the 5-HT1B RECEPTOR, but is expressed at low levels. It is particularly sensitive to the agonist SUMATRIPTAN and may be involved in mediating the drug's antimigrane effect.
5,7-Dihydroxytryptamine
Tryptamine substituted with two hydroxyl groups in positions 5 and 7. It is a neurotoxic serotonin analog that destroys serotonergic neurons preferentially and is used in neuropharmacology as a tool.
Biogenic Monoamines
Serotonin 5-HT3 Receptor Antagonists
Drugs that bind to but do not activate SEROTONIN 5-HT3 RECEPTORS, thereby blocking the actions of SEROTONIN or SEROTONIN 5-HT3 RECEPTOR AGONISTS.
Antidepressive Agents
Mood-stimulating drugs used primarily in the treatment of affective disorders and related conditions. Several MONOAMINE OXIDASE INHIBITORS are useful as antidepressants apparently as a long-term consequence of their modulation of catecholamine levels. The tricyclic compounds useful as antidepressive agents (ANTIDEPRESSIVE AGENTS, TRICYCLIC) also appear to act through brain catecholamine systems. A third group (ANTIDEPRESSIVE AGENTS, SECOND-GENERATION) is a diverse group of drugs including some that act specifically on serotonergic systems.
Fenfluramine
Cinanserin
A serotonin antagonist with limited antihistaminic, anticholinergic, and immunosuppressive activity.
Dopamine
One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.
Antidepressive Agents, Second-Generation
A structurally and mechanistically diverse group of drugs that are not tricyclics or monoamine oxidase inhibitors. The most clinically important appear to act selectively on serotonergic systems, especially by inhibiting serotonin reuptake.
N-Methyl-3,4-methylenedioxyamphetamine
An N-substituted amphetamine analog. It is a widely abused drug classified as a hallucinogen and causes marked, long-lasting changes in brain serotonergic systems. It is commonly referred to as MDMA or ecstasy.
Fluvoxamine
A selective serotonin reuptake inhibitor that is used in the treatment of DEPRESSION and a variety of ANXIETY DISORDERS.
Membrane Transport Proteins
Tryptamines
Decarboxylated monoamine derivatives of TRYPTOPHAN.
Monoamine Oxidase
An enzyme that catalyzes the oxidative deamination of naturally occurring monoamines. It is a flavin-containing enzyme that is localized in mitochondrial membranes, whether in nerve terminals, the liver, or other organs. Monoamine oxidase is important in regulating the metabolic degradation of catecholamines and serotonin in neural or target tissues. Hepatic monoamine oxidase has a crucial defensive role in inactivating circulating monoamines or those, such as tyramine, that originate in the gut and are absorbed into the portal circulation. (From Goodman and Gilman's, The Pharmacological Basis of Therapeutics, 8th ed, p415) EC 1.4.3.4.
Amphetamines
Brain
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Antidepressive Agents, Tricyclic
Substances that contain a fused three-ring moiety and are used in the treatment of depression. These drugs block the uptake of norepinephrine and serotonin into axon terminals and may block some subtypes of serotonin, adrenergic, and histamine receptors. However the mechanism of their antidepressant effects is not clear because the therapeutic effects usually take weeks to develop and may reflect compensatory changes in the central nervous system.
Cyproheptadine
Lysergic Acid Diethylamide
Semisynthetic derivative of ergot (Claviceps purpurea). It has complex effects on serotonergic systems including antagonism at some peripheral serotonin receptors, both agonist and antagonist actions at central nervous system serotonin receptors, and possibly effects on serotonin turnover. It is a potent hallucinogen, but the mechanisms of that effect are not well understood.
Rats, Sprague-Dawley
Tryptophan
An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.
Biogenic Amines
A group of naturally occurring amines derived by enzymatic decarboxylation of the natural amino acids. Many have powerful physiological effects (e.g., histamine, serotonin, epinephrine, tyramine). Those derived from aromatic amino acids, and also their synthetic analogs (e.g., amphetamine), are of use in pharmacology.
Sertraline
Blood Platelets
Imipramine
The prototypical tricyclic antidepressant. It has been used in major depression, dysthymia, bipolar depression, attention-deficit disorders, agoraphobia, and panic disorders. It has less sedative effect than some other members of this therapeutic group.
Clomipramine
A tricyclic antidepressant similar to IMIPRAMINE that selectively inhibits the uptake of serotonin in the brain. It is readily absorbed from the gastrointestinal tract and demethylated in the liver to form its primary active metabolite, desmethylclomipramine.
Piperazines
Piperazines are a class of heterocyclic organic compounds containing a seven-membered ring with two nitrogen atoms at positions 1 and 4, often used in pharmaceuticals as smooth muscle relaxants, antipsychotics, antidepressants, and antihistamines, but can also be found as recreational drugs with stimulant and entactogen properties.
Dose-Response Relationship, Drug
Norepinephrine Plasma Membrane Transport Proteins
Sodium chloride-dependent neurotransmitter symporters located primarily on the PLASMA MEMBRANE of noradrenergic neurons. They remove NOREPINEPHRINE from the EXTRACELLULAR SPACE by high affinity reuptake into PRESYNAPTIC TERMINALS. It regulates signal amplitude and duration at noradrenergic synapses and is the target of ADRENERGIC UPTAKE INHIBITORS.
Octopamine
An alpha-adrenergic sympathomimetic amine, biosynthesized from tyramine in the CNS and platelets and also in invertebrate nervous systems. It is used to treat hypotension and as a cardiotonic. The natural D(-) form is more potent than the L(+) form in producing cardiovascular adrenergic responses. It is also a neurotransmitter in some invertebrates.
Methiothepin
A serotonin receptor antagonist in the CENTRAL NERVOUS SYSTEM used as an antipsychotic.
p-Chloroamphetamine
Chlorinated analog of AMPHETAMINE. Potent neurotoxin that causes release and eventually depletion of serotonin in the CNS. It is used as a research tool.
Monoamine Oxidase Inhibitors
Ritanserin
A selective and potent serotonin-2 antagonist that is effective in the treatment of a variety of syndromes related to anxiety and depression. The drug also improves the subjective quality of sleep and decreases portal pressure.
Neurons
Microdialysis
Adrenergic Uptake Inhibitors
Drugs that block the transport of adrenergic transmitters into axon terminals or into storage vesicles within terminals. The tricyclic antidepressants (ANTIDEPRESSIVE AGENTS, TRICYCLIC) and amphetamines are among the therapeutically important drugs that may act via inhibition of adrenergic transport. Many of these drugs also block transport of serotonin.
Buspirone
An anxiolytic agent and serotonin receptor agonist belonging to the azaspirodecanedione class of compounds. Its structure is unrelated to those of the BENZODIAZAPINES, but it has an efficacy comparable to DIAZEPAM.
Serotonin 5-HT4 Receptor Antagonists
Drugs that bind to but do not activate SEROTONIN 5-HT4 RECEPTORS, thereby blocking the actions of SEROTONIN or SEROTONIN RECEPTOR AGONISTS.
Serotonin 5-HT3 Receptor Agonists
Endogenous compounds and drugs that specifically stimulate SEROTONIN 5-HT3 RECEPTORS.
Nerve Tissue Proteins
'Nerve tissue proteins' are specialized proteins found within the nervous system's biological tissue, including neurofilaments, neuronal cytoskeletal proteins, and neural cell adhesion molecules, which facilitate structural support, intracellular communication, and synaptic connectivity essential for proper neurological function.
Norepinephrine
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
Neurotransmitter Agents
Substances used for their pharmacological actions on any aspect of neurotransmitter systems. Neurotransmitter agents include agonists, antagonists, degradation inhibitors, uptake inhibitors, depleters, precursors, and modulators of receptor function.
Serotonin 5-HT4 Receptor Agonists
Endogenous compounds and drugs that specifically stimulate SEROTONIN 5-HT4 RECEPTORS.
Enterochromaffin Cells
A subtype of enteroendocrine cells found in the gastrointestinal MUCOSA, particularly in the glands of PYLORIC ANTRUM; DUODENUM; and ILEUM. These cells secrete mainly SEROTONIN and some neuropeptides. Their secretory granules stain readily with silver (argentaffin stain).
Brain Chemistry
Cyclohexanols
Metergoline
Vesicular Monoamine Transport Proteins
Hallucinogens
Drugs capable of inducing illusions, hallucinations, delusions, paranoid ideations, and other alterations of mood and thinking. Despite the name, the feature that distinguishes these agents from other classes of drugs is their capacity to induce states of altered perception, thought, and feeling that are not experienced otherwise.
Depressive Disorder
Dexfenfluramine
The S-isomer of FENFLURAMINE. It is a serotonin agonist and is used as an anorectic. Unlike fenfluramine, it does not possess any catecholamine agonist activity.
5,6-Dihydroxytryptamine
Tryptamine substituted with two hydroxyl groups in positions 5 and 6. It is a neurotoxic serotonin analog that destroys serotonergic neurons preferentially and is used in neuropharmacologic research.
Dopamine Plasma Membrane Transport Proteins
Sodium chloride-dependent neurotransmitter symporters located primarily on the PLASMA MEMBRANE of dopaminergic neurons. They remove DOPAMINE from the EXTRACELLULAR SPACE by high affinity reuptake into PRESYNAPTIC TERMINALS and are the target of DOPAMINE UPTAKE INHIBITORS.
Autoreceptors
Spiperone
Analysis of Variance
Neurotransmitter Uptake Inhibitors
Drugs that inhibit the transport of neurotransmitters into axon terminals or into storage vesicles within terminals. For many transmitters, uptake determines the time course of transmitter action so inhibiting uptake prolongs the activity of the transmitter. Blocking uptake may also deplete available transmitter stores. Many clinically important drugs are uptake inhibitors although the indirect reactions of the brain rather than the acute block of uptake itself is often responsible for the therapeutic effects.
Pineal Gland
A light-sensitive neuroendocrine organ attached to the roof of the THIRD VENTRICLE of the brain. The pineal gland secretes MELATONIN, other BIOGENIC AMINES and NEUROPEPTIDES.
Cocaine
An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake.
Polymorphism, Genetic
The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.
Rats, Wistar
Ganglia, Invertebrate
Clusters of neuronal cell bodies in invertebrates. Invertebrate ganglia may also contain neuronal processes and non-neuronal supporting cells. Many invertebrate ganglia are favorable subjects for research because they have small numbers of functional neuronal types which can be identified from one animal to another.
Mianserin
Pyridines
Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.
Drug Interactions
Aggression
Genotype
Carrier Proteins
Moclobemide
A reversible inhibitor of monoamine oxidase type A; (RIMA); (see MONOAMINE OXIDASE INHIBITORS) that has antidepressive properties.
Desipramine
A tricyclic dibenzazepine compound that potentiates neurotransmission. Desipramine selectively blocks reuptake of norepinephrine from the neural synapse, and also appears to impair serotonin transport. This compound also possesses minor anticholinergic activity, through its affinity to muscarinic receptors.
Depressive Disorder, Major
Marked depression appearing in the involution period and characterized by hallucinations, delusions, paranoia, and agitation.
Depression
Depressive states usually of moderate intensity in contrast with major depression present in neurotic and psychotic disorders.
Aminopyridines
Prefrontal Cortex
The rostral part of the frontal lobe, bounded by the inferior precentral fissure in humans, which receives projection fibers from the MEDIODORSAL NUCLEUS OF THE THALAMUS. The prefrontal cortex receives afferent fibers from numerous structures of the DIENCEPHALON; MESENCEPHALON; and LIMBIC SYSTEM as well as cortical afferents of visual, auditory, and somatic origin.
Histamine
Chromatography, High Pressure Liquid
Synaptic Transmission
The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.
Swimming
An activity in which the body is propelled through water by specific movement of the arms and/or the legs. Swimming as propulsion through water by the movement of limbs, tail, or fins of animals is often studied as a form of PHYSICAL EXERTION or endurance.
Homovanillic Acid
Homovanillic acid (HVA) is a major metabolite of dopamine, formed in the body through the catabolic breakdown of this neurotransmitter by the enzyme catechol-O-methyltransferase and then further metabolized in the liver before excretion in urine.
Radioligand Assay
Indoles
Pargyline
A monoamine oxidase inhibitor with antihypertensive properties.
Melatonin
A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.
Arylalkylamine N-Acetyltransferase
An acetyltransferase with specificity towards the amine group of aromatic alkylamines (arylalkylamines) such as SEROTONIN. This enzyme is also referred to as serotonin acetylase despite the fact that serotonin acetylation can also occur through the action of broad specificity acetyltransferases such as ARYLAMINE N-ACETYLTRANSFERASE.
Dopamine Uptake Inhibitors
Drugs that block the transport of DOPAMINE into axon terminals or into storage vesicles within terminals. Most of the ADRENERGIC UPTAKE INHIBITORS also inhibit dopamine uptake.
Hippocampus
A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.
Antipsychotic Agents
Agents that control agitated psychotic behavior, alleviate acute psychotic states, reduce psychotic symptoms, and exert a quieting effect. They are used in SCHIZOPHRENIA; senile dementia; transient psychosis following surgery; or MYOCARDIAL INFARCTION; etc. These drugs are often referred to as neuroleptics alluding to the tendency to produce neurological side effects, but not all antipsychotics are likely to produce such effects. Many of these drugs may also be effective against nausea, emesis, and pruritus.
Fluorobenzenes
Platelet Aggregation
Malignant Carcinoid Syndrome
A symptom complex associated with CARCINOID TUMOR and characterized by attacks of severe flushing of the skin, diarrheal watery stools, bronchoconstriction, sudden drops in blood pressure, edema, and ascites. The carcinoid tumors are usually located in the gastrointestinal tract and metastasize to the liver. Symptoms are caused by tumor secretion of serotonin, prostaglandins, and other biologically active substances. Cardiac manifestations constitute CARCINOID HEART DISEASE. (Dorland, 27th ed; Stedman, 25th ed)
Ondansetron
A competitive serotonin type 3 receptor antagonist. It is effective in the treatment of nausea and vomiting caused by cytotoxic chemotherapy drugs, including cisplatin, and has reported anxiolytic and neuroleptic properties.
Anxiety
Feeling or emotion of dread, apprehension, and impending disaster but not disabling as with ANXIETY DISORDERS.
Clorgyline
Mice, Inbred C57BL
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
Brain Stem
The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.
Reserpine
An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use.
Mice, Knockout
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.