SB-277011-A
Encyclopedia
SB-277,011A is a drug which acts as a potent and selective dopamine
D3 receptor
antagonist
, which is around 80-100x selective for D3 over D2, and lacks any partial agonist
activity.
SB-277,011A is used in the study of addiction
to stimulant
drugs such as nicotine
and cocaine
. Where cocaine reduces the threshold for brain electrical self-stimulation in rats, an indication of cocaine's rewarding
effects, SB-277,011A completely reverses this effect. It may thus be useful in the treatment of addiction to nicotine and cocaine, and is also being investigated for potential uses in the treatment of other drug addictions, such as addiction to heroin and alcohol
.
Another potential application for SB-277,011A is in the treatment of schizophrenia
, and it may be particularly useful in treating comorbid patients who are both schizophrenic and addicted to drugs. However it may worsen side effects such as tardive dyskinesia
in patients who are already prescribed antipsychotic
drugs.
Dopamine
Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this substituted phenethylamine functions as a neurotransmitter, activating the five known types of dopamine receptors—D1, D2, D3, D4, and D5—and their...
D3 receptor
Dopamine receptor D3
D dopamine receptor is a protein that in humans is encoded by the DRD3 gene.This gene encodes the D3 subtype of the dopamine receptor. The D3 subtype inhibits adenylyl cyclase through inhibitory G-proteins. This receptor is expressed in phylogenetically older regions of the brain, suggesting that...
antagonist
Receptor antagonist
A receptor antagonist is a type of receptor ligand or drug that does not provoke a biological response itself upon binding to a receptor, but blocks or dampens agonist-mediated responses...
, which is around 80-100x selective for D3 over D2, and lacks any partial agonist
Partial agonist
Partial agonists bind and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist...
activity.
SB-277,011A is used in the study of addiction
Substance dependence
The section about substance dependence in the Diagnostic and Statistical Manual of Mental Disorders does not use the word addiction at all. It explains:...
to stimulant
Stimulant
Stimulants are psychoactive drugs which induce temporary improvements in either mental or physical function or both. Examples of these kinds of effects may include enhanced alertness, wakefulness, and locomotion, among others...
drugs such as nicotine
Nicotine
Nicotine is an alkaloid found in the nightshade family of plants that constitutes approximately 0.6–3.0% of the dry weight of tobacco, with biosynthesis taking place in the roots and accumulation occurring in the leaves...
and cocaine
Cocaine
Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system, an appetite suppressant, and a topical anesthetic...
. Where cocaine reduces the threshold for brain electrical self-stimulation in rats, an indication of cocaine's rewarding
Reward system
In neuroscience, the reward system is a collection of brain structures which attempts to regulate and control behavior by inducing pleasurable effects...
effects, SB-277,011A completely reverses this effect. It may thus be useful in the treatment of addiction to nicotine and cocaine, and is also being investigated for potential uses in the treatment of other drug addictions, such as addiction to heroin and alcohol
Alcoholic beverage
An alcoholic beverage is a drink containing ethanol, commonly known as alcohol. Alcoholic beverages are divided into three general classes: beers, wines, and spirits. They are legally consumed in most countries, and over 100 countries have laws regulating their production, sale, and consumption...
.
Another potential application for SB-277,011A is in the treatment of schizophrenia
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
, and it may be particularly useful in treating comorbid patients who are both schizophrenic and addicted to drugs. However it may worsen side effects such as tardive dyskinesia
Tardive dyskinesia
Tardive dyskinesia is a difficult-to-treat form of dyskinesia that can be tardive...
in patients who are already prescribed antipsychotic
Antipsychotic
An antipsychotic is a tranquilizing psychiatric medication primarily used to manage psychosis , particularly in schizophrenia and bipolar disorder. A first generation of antipsychotics, known as typical antipsychotics, was discovered in the 1950s...
drugs.