Monoamine transporters (MATs) are proteins that function as integral plasma-membrane transporters to regulate concentrations of extracellular monoamine neurotransmitters. The three major classes are serotonin transporters (SERTs), dopamine transporters (DATs), and norepinephrine transporters (NETs) and are responsible for the reuptake of their associated amine neurotransmitters. MATs are located just outside the synaptic cleft (peri-synaptically), transporting monoamine transmitter overflow from the synaptic cleft back to the cytoplasm of the pre-synaptic neuron. MAT regulation generally occurs through protein phosphorylation and post-translational modification. Due to their significance in neuronal signaling, MATs are commonly associated with drugs used to treat mental disorders as well as recreational drugs. Compounds targeting MATs range from medications such as the wide variety of tricyclic antidepressants, selective serotonin reuptake inhibitors such as fluoxetine (Prozac) to stimulant medications such as methylphenidate (Ritalin) and amphetamine in its many forms and derivatives methamphetamine (Desoxyn) and lisdexamfetamine (Vyvanse). Furthermore, drugs such as MDMA and natural alkaloids such as cocaine exert their effects in part by their interaction with MATs, by blocking the transporters from mopping up dopamine, serotonin, and other neurotransmitters from the synapse.
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 dopamine not absorbed by the postsynaptic neuron is blocked from re-entering the presynaptic neuron. This results in increased extracellular concentrations of dopamine and increase in dopaminergic neurotransmission.
The dopamine transporter is a membrane-spanning protein coded for in humans by the SLC6A3 gene, that pumps the neurotransmitter dopamine out of the synaptic cleft back into cytosol. In the cytosol, other transporters sequester the dopamine into vesicles for storage and later release. Dopamine reuptake via DAT provides the primary mechanism through which dopamine is cleared from synapses, although there may be an exception in the prefrontal cortex, where evidence points to a possibly larger role of the norepinephrine transporter.
Phenylpiracetam, also known as fonturacetam and sold under the brand names Phenotropil, Actitropil, and Carphedon among others, is a stimulant and nootropic medication used in Russia and certain other Eastern European countries in the treatment of cerebrovascular deficiency, depression, apathy, and attention, and memory problems, among other indications. It is also used in Russian cosmonauts to improve physical, mental, and cognitive abilities. The drug is taken by mouth.
Dopaminergic means "related to dopamine", a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain.
(+)-CPCA is a stimulant drug similar in structure to pethidine and to RTI-31, but nocaine lacks the two-carbon bridge of RTI-31's tropane skeleton. This compound was first developed as a substitute agent for cocaine.
A monoamine releasing agent (MRA), or simply monoamine releaser, is a drug that induces the release of a monoamine neurotransmitter from the presynaptic neuron into the synapse, leading to an increase in the extracellular concentrations of the neurotransmitter. Many drugs induce their effects in the body and/or brain via the release of monoamine neurotransmitters, e.g., trace amines, many substituted amphetamines, and related compounds.
A eugeroic, or eugregoric, also known as a vigilance-promoting agent, is a type of drug that increases vigilance. The term has been used inconsistently and in multiple ways in the scientific literature, either to refer specifically to modafinil-type wakefulness-promoting agents or to refer to wakefulness-promoting agents generally. It was first introduced in the French literature in 1987 as a descriptor for modafinil-like wakefulness-promoting drugs and for purposes of distinguishing such drugs from psychostimulants. However, the term "eugeroic" has not been widely adopted in the literature, and instead the term "wakefulness-promoting agent" has been more widely used, both for modafinil-type drugs and other agents.
Flmodafinil, also known as bisfluoromodafinil and lauflumide, is a wakefulness-promoting agent related to modafinil which has been developed for treatment of a variety of different medical conditions. These include chronic fatigue syndrome, idiopathic hypersomnia, narcolepsy, attention deficit hyperactivity disorder (ADHD), and Alzheimer's disease. Aside its development as a potential pharmaceutical drug, flmodafinil is sold online and used non-medically as a nootropic.
JHW-007 is a cocaine analogue and a high affinity atypical dopamine reuptake inhibitor that is being researched for the treatment of cocaine addiction. JHW-007 has been found to blunt the psychostimulant effects of cocaine and reduce self-administration in rodents. JHW-007 exposure has been shown to block the conditioned place preference effects of cocaine. JHW-007 may directly antagonize the autoregulatory dopamine D2 receptor, a hypothesis that was developed following the observation of JHW-007's ability to inhibit D2 receptor-mediated currents in the midbrain.
Esmodafinil (also known as (S)-modafinil or (+)-modafinil; developmental code name CRL-40983) is the enantiopure (S)-(+)-enantiomer of modafinil. Unlike armodafinil ((R)-(–)-modafinil), esmodafinil has never been marketed on its own.
Modafiendz, also known as N-methyl-4,4-difluoromodafinil or as N-methylbisfluoromodafinil, is a wakefulness-promoting agent related to modafinil that was never marketed. It is sold online and used non-medically as a nootropic.
JJC8-088 is a dopamine reuptake inhibitor (DRI) that was derived from the wakefulness-promoting agent modafinil.
(S)-MK-26 is an atypical dopamine reuptake inhibitor (DRI) that was derived from modafinil. It is closely related to two other modafinil analogues, (S,S)-CE-158 and (S)-CE-123.
CE-158 is an atypical dopamine reuptake inhibitor (DRI) that was derived from modafinil. It is often but not always referred to as the enantiopure enantiomer (S,S)-CE-158 instead.
JJC8-016 is an atypical dopamine reuptake inhibitor (DRI) that was derived from modafinil. It was an early lead in the development of novel modafinil analogues with improved properties for potential use in the treatment of psychostimulant use disorder (PSUD).
JJC8-091 is an atypical dopamine reuptake inhibitor (DRI) that was derived from modafinil. It is a lead compound for potential treatment of psychostimulant use disorder (PSUD) and is under development by Encepheal Therapeutics for use as a pharmaceutical drug.
JJC8-089 is a dopamine reuptake inhibitor (DRI) that was derived from modafinil and is related to JJC8-016, JJC8-088, and JJC8-091. Its affinity (Ki) for the dopamine transporter (DAT) is 37.8 nM, for the norepinephrine transporter (NET) is 11,820 nM, for the serotonin transporter (SERT) is 6,800 nM, and for the sigma σ1 receptor is 2.24 nM. It also has significant affinity for several dopamine receptors. JJC8-089 has substantially higher affinity for the DAT than modafinil. The drug shows pro-motivational effects in animals. It was first described in the scientific literature by 2016.
