
Monoamine-depleting agents are a group of
drug
A drug is any chemical substance other than a nutrient or an essential dietary ingredient, which, when administered to a living organism, produces a biological effect. Consumption of drugs can be via insufflation (medicine), inhalation, drug i ...
s which reversibly deplete one or more of the
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 ...
s
serotonin
Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...
,
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. It is an amine synthesized ...
, and
norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic compound, organic chemical in the catecholamine family that functions in the brain and human body, body as a hormone, neurotransmitter and neuromodulator. The ...
.
One
mechanism
Mechanism may refer to:
*Mechanism (economics), a set of rules for a game designed to achieve a certain outcome
**Mechanism design, the study of such mechanisms
*Mechanism (engineering), rigid bodies connected by joints in order to accomplish a ...
by which these agents act is by
inhibiting reuptake
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 ...
by the
vesicular monoamine transporter
The vesicular monoamine transporter (VMAT) is a transport protein integrated into the membranes of synaptic vesicles of presynaptic neurons. It transports monoamine neurotransmitters – such as dopamine, serotonin, norepinephrine, epinephrin ...
s,
VMAT1
Vesicular monoamine transporter 1 (VMAT1), also known as chromaffin granule amine transporter (CGAT) or solute carrier family 18 member 1 (SLC18A1), is a protein that in humans is encoded by the ''SLC18A1'' gene. VMAT1 is an integral membrane pro ...
and
VMAT2
The solute carrier family 18 member 2 (SLC18A2) also known as vesicular monoamine transporter 2 (VMAT2) is a protein that in humans is encoded by the ''SLC18A2'' gene. VMAT2 is an integral membrane protein that transports monoamines—particul ...
.
Examples of monoamine-depleting agents include
deutetrabenazine
Deutetrabenazine (trade name Austedo) is a vesicular monoamine transporter 2 inhibitor which is used for the treatment of chorea associated with Huntington's disease and tardive dyskinesia.
Chemically, deutetrabenazine is an isotopic isomer o ...
,
methyldopa
Methyldopa, also known as α-methyl-L-DOPA and sold under the brand name Aldomet among others, is a medication used for high blood pressure. It is one of the preferred treatments for high blood pressure in pregnancy. For other types of high blo ...
,
oxypertine
Oxypertine, sold under the brand name Oxypertine among others, is an antipsychotic medication of the pertine group which was previously used in the treatment of schizophrenia but is no longer marketed. It was also evaluated for the treatment of ...
,
reserpine
Reserpine is a drug that is used for the treatment of hypertension, high blood pressure, usually in combination with a thiazide diuretic or vasodilator. Large clinical trials have shown that combined treatment with reserpine plus a thiazide diur ...
,
tetrabenazine
Tetrabenazine is a drug for the symptomatic treatment of hyperkinetic movement disorders. It is sold under the brand names Nitoman and Xenazine among others. On August 15, 2008, the US Food and Drug Administration (FDA) approved the use of tet ...
,
and
valbenazine
Valbenazine, sold under the brand name Ingrezza, is a medication used to treat tardive dyskinesia. It acts as a vesicular monoamine transporter 2 (VMAT2) inhibitor.
Medical use
Valbenazine is used to treat tardive dyskinesia in adults. Tardive ...
.
Tetrabenazine selectively depletes dopamine at low doses and is used as an
animal model
An animal model (short for animal disease model) is a living, non-human, often genetic-engineered animal used during the research and investigation of human disease, for the purpose of better understanding the disease process without the risk of ha ...
of
amotivation
Amotivational syndrome is a chronic psychiatric disorder characterized by signs that are linked to cognitive and emotional states such as detachment, blunted emotion and drives, executive functions like memory and attention, disinterest, passivi ...
.
Monoamine synthesis inhibitors, such as the
tryptophan hydroxylase
Tryptophan hydroxylase (TPH) is an enzyme () involved in the synthesis of the monoamine neurotransmitter serotonin. Tyrosine hydroxylase, phenylalanine hydroxylase, and tryptophan hydroxylase together constitute the family of biopterin-depen ...
inhibitor
Inhibitor or inhibition may refer to:
Biology
* Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity
* Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotransmi ...
and serotonin synthesis inhibitor
''para''-chlorophenylalanine (PCPA or fenclonine), also act as monoamine-depleting agents, as do various other agents, for instance
monoaminergic neurotoxin
A monoamine neurotoxin, or monoaminergic neurotoxin, is a drug that selectively damages or destroys monoaminergic neurons. Monoaminergic neurons are neurons that signal via stimulation by monoamine neurotransmitters including serotonin, dopamine ...
s.
See also
*
Monoamine reuptake inhibitor
A monoamine reuptake inhibitor (MRI) is a drug that acts as a reuptake inhibitor of one or more of the three major monoamine neurotransmitters serotonin, norepinephrine, and dopamine by blocking the action of one or more of the respective monoamin ...
*
Monoamine releasing agent
A monoamine releasing agent (MRA), or simply monoamine releaser, is a drug that induces the release of one or more monoamine neurotransmitters from the presynaptic neuron into the synapse, leading to an increase in the extracellular concentrati ...
*
Tetrabenazine § Animal model of motivational dysfunction
References
{{Monoamine reuptake inhibitors
Monoamine-depleting agents
VMAT inhibitors