Dopamine receptor D2, is a protein that is encoded by the DRD2 gene.
It suggested that dopamine receptors are the site of action of antipsychotic drugs.
This gene encodes the D2 subtype of the dopamine receptor, which is coupled to Gi subtype of G protein-coupled receptor.
The G protein-coupled receptor inhibits adenylyl cyclase activity.
D2R is involved in retrieval of fear memories in the prelimbic cortex.
D2R that mediates the cognitive flexibility in humans.
The long form (D2Lh) functions as a classic post-synaptic receptor.
The short form (D2Sh) is pre-synaptic and functions as an autoreceptor that regulates the levels of dopamine in the synaptic cleft.
Agonists of D2sh receptors inhibitdopamine release.
Antagonist increases dopaminergic release.
Disorders in the equilibration of D2R state, causes problems in signal transf2242ing between the nervous systems.
DR2 disequilibrium may lead to disorders, such as Schizophrenia, autism and Parkinson’s disease.
To control such disorders, equilibration between the D2R states is controlled by implementing of agonist and antagonist D2R ligands.
Problems regarding the D2R states may have genetic origins.
D2R abnormal states are controlled by drug therapy.
Most of the older antipsychotic drugs such as chlorpromazine and haloperidol are antagonists for the dopamine D2 receptor, but are very unselective.
Bromocriptine – full agonist
Ropinirole – full agonist
LSD – a partial agonist and potentiates dopamine-mediated prolactin secretion in lactotrophs.
Domperidone – D2 and D3 antagonist; does not cross the blood-brain barrier
Metoclopramide – Antiemetic