Dopamine
Dopamine is a monoamine neurotransmitter found in many animals including humans. Chemically, it is a phenethylamine and it is related to norepinephrine and epinephrine. Its action in the brain leads to effects such as excitement, inspiration, motivation, pleasure, euphoria, alertness, focus, impulsive behaviour and loss of appetite. It is commonly associated with the reward system of the brain, and is thought to play a key role in reinforcement and addiction. Dopaminergic dysfunction can lead to problems in congnition, learning, working memory, voluntary movement, sleep, mood and other areas, manifested in conditions such as Parkinson's disease, autism, ADHD and schizophrenia. It is a catecholamine
It's a common misconception that "dope" derives from dopamine. The word dope has been in the English language since approximately 1807 and comes from the Dutch doop meaning a thick dipping sauce. It has been used to describe someone who is stupid or thick headed since about the 1850s and has been used to refer to semi-liquid opium since the 1880s. The word dopamine, on the other hand, comes from its biological precursor, DOPA (dihydroxyphenylalanine), which is turned into dopamine with CO2 with DOPA decarboxylase. The more you know.
Virtually all recreational drugs have pro-dopaminergic effects in some way:
Examples of dopaminergic substances
Biosynthetic precursors:
- L-Dopa used in Parkinson's and other disorders.
- L-Tyrosine
- L-Phenylalanine
Metabolic products:
Stimulants:
Reuptake inhibitors:
- Cocaine an SNDRI (serotonin-dopamine-norepinephrine reuptake inhibitor or [[triple reuptake inhibi[tor]]
- Methylphenidate - an NDRI well known for its use in ADHD treatment. MPH's brother Ethylphenidate has similar profile, with lessened efficacy for the NAT
- MDPV - a potent NDRI that is predominantly selective for dopamine
- Ketamine - acts as a DRI in addition to it's dissociative action. Also a D2 agonist.
- PCP
- MXE
- Modafinil
- Buproprion
Releasing agents:
- Amphetamine - primarily a dopamine/norepinephrine releasing agent with small effect on serotonin
- Methamphetamine
- MDMA - primarily a releaser of serotonin and norepinephrine
- Mephedrone - powerful releaser of serotonin (comparable to MDMA) and dopamine (comparable to amphetamine)
- Ephedrine - releasing agent, with adrenergic action being dominant mode of effect
- 4-MAR - 4-methyl-aminorex, a rare drug of semi-mythical status comparable to methamphetamine
- Phenmetrazine
Receptor agonists:
- Apomorphine D2/D3 agonist, active component of blue lotus
- LSD has affinity for all receptor subtypes, notably D2
- Salvia has potent activity at D2 as a partial agonist, greater than even it's remarkably potent action on kappa opioid receptors
- Ketamine D2 agonism
Indirect agents:
Dopamine antagonists:
Many antipsychotics act as dopamine antagonists, and are generally somewhat selective for the D2 subtype. Some also act as 5-ht2a receptor antagonists.
Antipsychotics are not considered to have recreational effects by almost everyone. Their main use among recreational drug users (aside from their prescribed purpose, is often as a sleep inducing agent or in an attempt to abort a trip. Users should be aware of the unpleasant, even destructive side effects they can cause (eg. neuroleptic malignant syndrome)
Receptor subtypes: Dopamine receptors are often divided into two groups, D1-like receptors and D2-like receptors
D1-like receptors:
D2-like receptors:
See Also
Other endogenous neurotransmitters:
Relevant biochemistry:
Mental Health:
Other:
