A monoamine reuptake inhibitor (MRI) is a

drug A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhala ...

that acts as a

reuptake inhibitor Reuptake is the reabsorption of a neurotransmitter by a neurotransmitter transporter located along the plasma membrane of an axon terminal (i.e., the pre-synaptic neuron at a synapse) or glial cell after it has performed its function of transmi ...

of one or more of the three major

monoamine neurotransmitter Monoamine neurotransmitters are neurotransmitters and neuromodulators that contain one amino group connected to an aromatic ring by a two-carbon chain (such as -CH2-CH2-). Examples are dopamine, norepinephrine and serotonin. All monoamines ar ...

serotonin Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and va ...

norepinephrine Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad ...

, and

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 80% o ...

by blocking the action of one or more of the respective

monoamine transporter Monoamine transporters (MATs) are protein structures that function as integral plasma-membrane transporters to regulate concentrations of extracellular monoamine neurotransmitters. Three major classes of MATs (SERT, DAT, NET) are responsible fo ...

s (MATs), which include the

serotonin transporter The serotonin transporter (SERT or 5-HTT) also known as the sodium-dependent serotonin transporter and solute carrier family 6 member 4 is a protein that in humans is encoded by the SLC6A4 gene. SERT is a type of monoamine transporter protein tha ...

(SERT),

norepinephrine transporter The norepinephrine transporter (NET), also known as noradrenaline transporter (NAT), is a protein that in humans is encoded by the solute carrier family 6 member 2 (SLC6A2) gene. NET is a monoamine transporter and is responsible for the sodium- ...

(NET), and

dopamine transporter The dopamine transporter (also dopamine active transporter, DAT, SLC6A3) is a membrane-spanning protein that pumps the neurotransmitter dopamine out of the synaptic cleft back into cytosol. In the cytosol, other transporters sequester the dop ...

(DAT). This in turn results in an increase in the synaptic

concentration In chemistry, concentration is the abundance of a constituent divided by the total volume of a mixture. Several types of mathematical description can be distinguished: '' mass concentration'', '' molar concentration'', ''number concentration'', ...

s of one or more of these neurotransmitters and therefore an increase in

monoaminergic Monoaminergic means "working on monoamine neurotransmitters", which include serotonin, dopamine, norepinephrine, epinephrine, and histamine. A monoaminergic, or monoaminergic drug, is a chemical, which functions to directly modulate the ser ...

neurotransmission Neurotransmission (Latin: ''transmissio'' "passage, crossing" from ''transmittere'' "send, let through") is the process by which signaling molecules called neurotransmitters are released by the axon terminal of a neuron (the presynaptic neuron), ...

Uses

The majority of currently approved

antidepressant Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common Side effect, side-effects of antidepressants include Xerostomia, dry mouth, weig ...

s act predominantly or exclusively as MRIs, including the

selective serotonin reuptake inhibitor Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs increase the extracellul ...

s (SSRIs),

serotonin–norepinephrine reuptake inhibitor Serotonin–norepinephrine reuptake inhibitors (SNRIs) are a class of antidepressant drugs used to treat major depressive disorder (MDD), anxiety disorders, obsessive–compulsive disorder (OCD), social phobia, attention-deficit hyperactivity di ...

s (SNRIs), and almost all of the

tricyclic antidepressant Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...

s (TCAs). Many

psychostimulant Stimulants (also often referred to as psychostimulants or colloquially as uppers) is an overarching term that covers many drugs including those that increase activity of the central nervous system and the body, drugs that are pleasurable and inv ...

s used either in the treatment of or as

appetite suppressant An anorectic or anorexic is a drug which reduces appetite, resulting in lower food consumption, leading to weight loss. By contrast, an appetite stimulant is referred to as orexigenic. The term is (from the Greek ''ἀν-'' (an-) = "without" ...

s in the treatment of

obesity Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's ...

also behave as MRIs, although notably amphetamine (and methamphetamine), which do act to some extent as monoamine reuptake inhibitors, exerts their effects primarily as releasing agents. Additionally, psychostimulants acting as MRIs that affect dopamine such as

cocaine Cocaine (from , from , ultimately from Quechua: ''kúka'') is a central nervous system (CNS) stimulant mainly used recreationally for its euphoric effects. It is primarily obtained from the leaves of two Coca species native to South Am ...

and

methylphenidate Methylphenidate, sold under the brand names Ritalin and Concerta among others, is the most widely prescribed central nervous system (CNS) stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and, to a lesser extent ...

are often abused as

recreational drug Recreational drug use indicates the use of one or more psychoactive drugs to induce an altered state of consciousness either for pleasure or for some other casual purpose or pastime by modifying the perceptions and emotions of the user. When a ...

s. As a result, many of them have become

controlled substance A controlled substance is generally a drug or chemical whose manufacture, possession and use is regulated by a government, such as illicitly used drugs or prescription medications that are designated by law. Some treaties, notably the Single ...

s, which in turn has resulted in the clandestine synthesis of a vast array of

designer drug A designer drug is a structural or functional analog of a controlled substance that has been designed to mimic the pharmacological effects of the original drug, while avoiding classification as illegal and/or detection in standard drug tests. D ...

s for the purpose of bypassing

drug law The prohibition of drugs through sumptuary legislation or religious law is a common means of attempting to prevent the recreational use of certain intoxicating substances. While some drugs are illegal to possess, many governments regulate the ...

s; a prime example of such is the mixed monoamine reuptake inhibitor and

releasing agent A monoamine releasing agent (MRA), or simply monoamine releaser, is a drug that induces the synapse, release of a monoamine neurotransmitter from the synapse, presynaptic neuron into the synapse, leading to an increase in the extracellular conc ...

mephedrone Mephedrone, also known as , , and , is a synthetic stimulant drug of the amphetamine and cathinone classes. Slang names include drone, , White Magic, meow meow, bubble, ''txomin'' and yurrpt. It is chemically similar to the cathinone compounds ...

Types of MRIs

There are a variety of different kinds of MRIs, of which include the following: * Specific for one monoamine transporter **

Serotonin reuptake inhibitor A serotonin reuptake inhibitor (SRI) is a type of drug which acts as a reuptake inhibitor of the neurotransmitter serotonin (5-hydroxytryptamine, or 5-HT) by blocking the action of the serotonin transporter (SERT). This in turn leads to incre ...

(SRI) ***

Selective serotonin reuptake inhibitor Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs increase the extracellul ...

(SSRI) **

Norepinephrine reuptake inhibitor A norepinephrine reuptake inhibitor (NRI, NERI) or noradrenaline reuptake inhibitor or adrenergic reuptake inhibitor (ARI), is a type of drug that acts as a reuptake inhibitor for the neurotransmitters norepinephrine (noradrenaline) and ep ...

(NRI) ***

Selective norepinephrine reuptake inhibitor Selective norepinephrine reuptake inhibitors (sNRIs) are a class of drugs that have been marketed as antidepressants and are used for various mental disorders, mainly depression and attention-deficit hyperactivity disorder (ADHD). The norepinephrin ...

(sNRI) **

Dopamine reuptake inhibitor A dopamine reuptake inhibitor (DRI) is a class of drug which acts as a reuptake inhibitor of the monoamine neurotransmitter dopamine by blocking the action of the dopamine transporter (DAT). Reuptake inhibition is achieved when extracellular ...

(DRI) * Non-specific, binding to two or more monoamine transporters **

Serotonin–norepinephrine reuptake inhibitor Serotonin–norepinephrine reuptake inhibitors (SNRIs) are a class of antidepressant drugs used to treat major depressive disorder (MDD), anxiety disorders, obsessive–compulsive disorder (OCD), social phobia, attention-deficit hyperactivity di ...

(SNRI) **

Serotonin–dopamine reuptake inhibitor A serotonin–dopamine reuptake inhibitor (SDRI) is a type of drug which acts as a reuptake inhibitor of the monoamine neurotransmitters serotonin and dopamine by blocking the actions of the serotonin transporter (SERT) and dopamine transporter ( ...

(SDRI) ** Norepinephrine–dopamine reuptake inhibitor (NDRI) **

Serotonin–norepinephrine–dopamine reuptake inhibitor A serotonin–norepinephrine–dopamine reuptake inhibitor (SNDRI), also known as a triple reuptake inhibitor (TRI), is a type of drug that acts as a combined reuptake inhibitor of the monoamine neurotransmitters serotonin, norepinephrine, a ...

Uses

Types of MRIs

Binding profiles

See also

References

External links