CPT1: Placebo Flashcards
What is a placebo?
A dummy medicine which contains no active ingreedient and is used in control trials
What conditions can placebos be used for?
- Parkinsons
- Depressions
- pain
- Angina
What is the placebo effect modulated by?
- colour: pink better for mainitaing concentration than blue
- Number of pills: increasing increases effect
- Behaviour of person giving placebo
- Price: mor expensive = better effect
- Capulses more effective than pills
- Brand name
What is the nocebo effect?
Telling someone the negative side effects of a placebo will increase the negative symptoms they experience
What is addiction?
- seeking to take a drug. loss of control with limited intake. Negative impact if can’t take it
What does addiction/ abuse involve?
Changes in compulsion and impulse control
What is intoxication/ binge?
Acute positive reinfocement - hedonistic- reward pathways
What is withdrawl/ negative symptoms?
negative emotion state and negative reinforcement
Preoccupation/ anticipation
Craving
What does effecting dopamine levels do?
Drug induced changes in dopamine levels result in sensation of reward.
Sensation of reward is associated with FAST not slow changes in dopamine
What drugs effect dopamine levels?
- Amphetamines
- nicotine
- morphine
- cocaine
How do amphetamines effect dopamine release?
- taken up by DAT and inserted into vesicle by VMAT. This releases dopamine into cytosol and modifies phosphorylation so DAT runs backwards
How does cocaine effect dopamine release?
Blocks DAT so dopamine in synaptic cleft increases
What happens during tolerance?
When receptor bound to agonists it desensitises and internalises it. This means it isn’t available on the membrane and availability of receptors is less. More drug is needed for same effect
How does morphine modulate pain?
- Inhibits peripheral nocioceptors responses
- Inhibits Ca2+ release from presynaptic terminals reducing NT release
- Enhances K+ channel activity at post synaptic membrane reducing membrane excitbaility
