Amphetamines Flashcards
What is the difference between what cocaine and amphetamine microinjections into the nucleus accumbens do to animals?
Amphetamine microinjections have a reinforcing effect, whereas cocaine microinjections don’t.
What family is amphetamine part of?
Synthetic psychostimulants related to dopamine.
Name the synthetic psychostimulants.
Amphetamine, methamphetamine, ephedrine, cathinone, MDMA, MDA, MDE.
Which synthetic psychostimulants have been used in plant form?
Cathinone - khat.
Ephedrine - ephedra vulgaris, a herbal remedy.
What dopamine pathway does amphetamine primarily affect?
The nigrostriatal pathway.
What have been the uses of ephedra?
- It was used as a herbal remedy for 5000 years, as it decreases appetite and provides a feeling of heightened energy.
- Was used as an appetite suppressant (now banned)
- Used for asthma in 1920s, led to amphetamine inhaler
- Later marketed for narcolepsy.
What is pseudoephedrine used for?
As a bronchodilator.
What is amphetamine used to treat?
ADHD - Ritalin.
What do amphetamines do on a neuronal level?
- They’re indirect dopamine agonists
- At high doses they inhibit catecholamine metabolism by monoamine oxidase (MAOA)
- Reverse dopamine transporters = extra release and no reuptake, also provokes release
- Also noradrenaline release
Which is stronger out of amphetamine and methamphetamine?
Methamphetamine
What is the elimination half-life of amphetamine?
7-30 hours, but some users take repeated IV injections every few hours over a period of days.
What did Griffith et al (1972) do?
Gave 7 pts (users w/no history of psychosis) dextroamphetamine every hour for up to 5 days.
What did Griffth et al (1972) find?
All the participants became psychotic within 2-5 days, with delusions mostly auditory but also included poisoning by the experimenters and electric dynamo thought control.
What is dextroamphetamine commonly known as?
Speed.
What are the adverse effects of amphetamines?
- Psychotic reactions (delusional beliefs, methamphetamine violence and flashbacks).
- Neurotoxicity (reduced TH, DA and DAT density, ecstasy affects 5-HT).