Dopamine is a neurotransmitter which upon binding to its receptor releases various downstream signals. Dopamine receptors are a class of G protein coupled receptor and can be found mainly in CNS of vertebrates. These receptors can be classified mainly in two sub classes- D1 like family and D2 like family. D1 like family consists of two GPCRs- D1 & D5 In these receptors dopamine binds to the G stimulatory sites and increases intracellular level of cAMP by activating adenylyl cyclase. D1 receptors are encoded by the gene DRD1 and can be found in Adrenal cortex, heart, kidney and seminal vesicles. This receptor acts in the function of Locomotion, learning and memory, attention, impulse control, Sleep & regulation of renal function Pregolide, amorphine are some agonists of this receptor where as many typical and atypical antipsychotics acts as antagonists. On the other hand D5 receptors are encoded by DRD5 gene and found in Cortex, substantia nigra and hypothalamus. This receptor involves in the function of Cognition, attention, decision making, motor learning and renin secretion. Fenoldopam and rotigonite are some agonists of these receptor. D2 like family consists of three GPCRs- D2, D3 & D4 In these receptors dopamine binds to the G inhibitory sites and decreases intracellular level of cAMP by inhibiting adenylyl cyclase. D2 receptors are encoded by DRD2 gene and found in Pituitary, substantia nigra, ventral tegmental area, and adrenal cortex. These receptors are involved in Locomotion, learning and memory, attention, sleep and reproductive behaviour. Talipexole and piribedil are some agonists and itopride, domperidone are some antagonists of these receptor. D3 receptor is encoded by gene DRD3 and is prominent in Striatum, islands of Calleja and cortex. This recepton has role in the function of Locomotion, cognition, attention, impulse control, sleep and regulation of food intake. Agonists of this receptor are dopamine, captodiam, pregolide etc. where as most antippycotics acts as antagonist. D4 receptors are expressed by the gene DRD4 and are found in Frontal cortex, amygdala, hypothalamus, and nucleus accumbens. This receptors are involved in Cognition, impulse control, attention, sleep and reproductive behaviour. These are the agonists and antagonists of this receptor. Dopamine is produced from amino acid tyrosine. Tyrosine is converted to DOPA by the enzyme tyrosine hydroxylase. Then DOPA is converted to dopamine by the enzyme DOPA decarboxylase. This dopamine is packed and stored into the synaptic vesicles VIA vesicular monoamine transporter. Until its released into the synaps. Dopamine has 4 pathways in the brain…..

1. Dopamine Receptor
NAME- DEBARUN GHOSH
ROLL NO.- 2014085
UNIVERSITY ROLL- 18920220003
UNIVERSITY RESGISTRATION NO.- 202892320210013 OF 2020-2021
Dr. B. C. Roy College of Pharmacy & AHS, Durgapur, West Bengal 1

2. Contents
1. Introduction
2. Subtypes of Dopamine Receptors
3. D1 Like Family (D1 and D5)
4. D2 Like Family (D2, D3 and D4)
5. Dopamine Production
6. 4 Dopaminergic Pathways in Brain
7. Dopamine Receptor in Disease
8. Conclusion
9. References
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3. Introduction
Dopamine is a monoamine neurotransmitter that upon binding to its
receptor releases a verity of downstream signals, leading to
chemical reactions in cells ultimately reaching the target.
Dopamine receptors are a class of G protein-coupled receptors.
These receptors are prominent mainly in CNS of vertebrate
Structure of dopamine receptor
(Source:https://proteopedia.org/wiki/index.php
/Dopamine_Receptors)
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4. Subtypes of Dopamine Receptors
4
Dopamine
Receptors
D1 Like
Family
D1 D5
D2 Like
Family
D2 D3 D4

5. D1 Like Family
•The D1-like subfamily consists of two G protein–coupled receptors D1 and D5.
• These are coupled to Gs, activates the adenylyl cyclase, leading to increase in concentration of
cAMP
•Mediate excitatory neurotransmission.
•These receptor genes do not contain introns in their coding sequence.
5

6. Encoding
Gene
Tissue
Distribution
Function Mechanism Agonists Antagonists
DRD1
Adrenal
cortex, heart,
kidney,
seminal
vesicles
Locomotion,
learning and
memory, attention,
impulse control,
sleep, regulation of
renal function
Increased
intracellular level of
cAMP by activated
adenylyl cyclase
apomorphine,
pergolide,
rotigotine,
terguride etc.
Many typical
and atypical
antipsychotics.
Ecopipam is a
selective D1-like
receptor
antagonist.
D1 Receptor
D5 Receptor
Encoding
Gene
Tissue
Distribution
Function Mechanism Agonists Antagonists
DRD5
Cortex,
substantia
nigra,
hypothalamus
Cognition,
attention,
decision making,
motor learning,
renin secretion
Adenylyl
cyclase↑
Dihydrexidine,
Rotigotine,
Stepholidine,
Fenoldopam etc.
• 4-Chloro-7-methyl-
5,6,7,8,9,14-
hexahydrodibenz[d,
g]azecin-3-ol
• SCH 23390
6

7. D2 Like Family
•The D2-like subfamily consists of three G protein–coupled receptors D2, D3 and D4.
•These are coupled to Gi, inhibits the adenylyl cyclase, leading to decrease in concentration of
cAMP.
•Mediate inhibitory neurotransmission.
•Those genes that encodes these receptors, contain introns.
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8. D2 Receptor
D3 Receptor
Encoding
Gene
Tissue
Distribution
Function Mechanism Agonists Antagonists
DRD2 Pituitary,
substantia
nigra, ventral
tegmental
area, adrenal
cortex.
Locomotion, learning
and memory,
attention,
sleep, reproductive
behaviour
Inhibit adenylyl
cyclase activity.
Talipexole,
Bromocriptine,
Piribedil,
Quinelorane etc.
Eticlopride,
Fallypride,
Hydroxyzine,
Itopride,
Domperidone,
Cinnarizine etc.
Encoding
Gene
Tissue
Distribution
Function Mechanism Agonists Antagonists
DRD3
Striatum,
islands of
Calleja,
cortex
Locomotion,
cognition, attention,
impulse control,
sleep, regulation of
food intake
Adenylyl cyclase↓ 5-OH-DPAT, 7-
OH-DPAT,
Pergolide,
Dopamine,
Captodiame etc.
Most
Antipsychotics,
Domperidone,
Nafadotride,
Haloperidol etc.
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9. Encoding
Gene
Tissue
Distribution
Function Mechanism Agonists Antagonists
DRD4 Frontal cortex,
amygdala,
hypothalamus,
nucleus
accumbens
Cognition, impulse
control, attention,
sleep, reproductive
behaviour
Adenylyl
cyclase↓
A-412997, ABT-670,
PD-168077,
Roxindole
A-381393,
FAUC213, L-745870,
L-750667,
olanzapine
D4 Receptor
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10. Production of Dopamine
10
Tyrosine
DOPA
Dopamine
TH
DOPADC

11. 4 Dopaminergic Pathways in Brain
1. The Mesolimbic Pathway
• The pathway projects from the ventral tegmental area (VTA) to
the nucleus accumbens in the limbic system.
• Associated with reward and schizophrenia
2. The Mesocortical Pathway
• Projects from the VTA to the prefrontal cortex.
• Associated with cognition and behavior.
3. The Nigrostriatal Pathway
• Projects from the dopaminergic neurons in the substantia
nigra to the basal ganglia or striatum.
• The nigrostriatal pathway mediates motor movements.
4.The Tuberoinfundibular (TI) Pathway
• Projects from the hypothalamus to the anterior pituitary.
• The TI pathway inhibits prolactin release.
Fig: Dopaminargic Pathway
Source:
https://i.pinimg.com/originals/15/79/18/15791
8ad58d566f4f15c6663b99af6f0.jpg
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12. Dopamine Receptors in Disease
• Parkinson’s Disease (Caused by loss of
dopaminergic nurons in SN)
• Schizophrenia (Due to hyperactive
dopaminergic signal transduction)
• ADHD (Due to decrease level of
dopamine)
• Addiction ADHD
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13. Conclusion
•Dopamine and dopamine receptor plays a very important role in our daily life.
•This hormone and its receptors affect movement, emotions and the reward system in the brain.
•Clear knowledge about this receptor will help us to treat various psychiatric disorder.
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14. References
•Beaulieu JM, Espinoza S, Gainetdinov RR (2015). "Dopamine receptors – IUPHAR Review 13". Br. J.
Pharmacol. 172 (1): 1–23. doi:10.1111/bph.12906. PMC 4280963. PMID 25671228.
•Paul ML, Graybiel AM, David JC, Robertson HA (October 1992). "D1-like and D2-like dopamine receptors
synergistically activate rotation and c-fos expression in the dopaminedepleted striatum in a rat model of
Parkinson's disease". The Journal of Neuroscience. 12 (10): 3729–42. PMC 6575976. PMID 1357113.
•Girault JA, Greengard P (2004). "The neurobiology of dopamine signaling". Arch. Neurol. 61 (5): 641–4.
doi:10.1001/archneur.61.5.641. PMID 15148138.
•Kienast T, Heinz A (2006). "Dopamine and the diseased brain". CNS Neurol Disord Drug Targets. 5
(1):109–31. doi:10.2174/187152706784111560. PMID 16613557.
•Mishra A, Singh S, Shukla S. Physiological and Functional Basis of Dopamine Receptors and Their Role
inNeurogenesis: Possible Implication for Parkinson's disease. J Exp Neurosci.
2018;12:1179069518779829. [PMCfree article: PMC5985548] [PubMed: 29899667]
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