5.8 Pharmacology Of Psychostimulant Misuse Flashcards
What do psychostimulants do to the CNS?
Activate the CNS resulting in alertness, excitation, and elevated mood
What is the MOA of nicotine?
- Nicotine activates nicotinic acetylcholinergic receptor
- Na enters cell, K exits the cell —> action potential
What determines how many molecules of Ach bind to receptor (in the MOA of nicotine)?
Heterogeneity of subunits
What may influence physiological response of nicotine?
Variation in receptor composition at different sites
What are the similarities between nicotine and ACh?
- Charged amino groups
- Hydrogen bond acceptor groups
When is nicotine membrane penetrable?
At physiological pH (weak base)
Is nicotine degraded by acetylcholinesterase?
No
What does partial agonist therapy cause?
Causes release of dopamine
What is a danger of partial agonist therapy?
Highly addictive
Nicotine replacement therapy is relatively ineffective alone. What increases the quit rate success?
Varenicline is a partial agonist that increases quit rate success
What is the MOA of cocaine?
- Antagonist of amine transporters: DAT, SERT, NERT
- Prevents DA uptake
- Increases DA concentration
- Increase duration of DA action
What is the order of preference for amine transporter antagonism of cocaine?
DAT >= SERT > NERT
What is the MOA of methamphetamine, ecstasy (XTC), and bath salts?
Compete for reuptake
- Resemble endogenous DA, NE
- Block DA reuptake
- Push out DA from vesicles
- Increase extra-vesicular DA
- Reverse transport (gradient)
Activate trace amine-associated receptor (TAAR1)
- Phosphorylates DAT
- Induces reverse transport fxn
What are neurological effects of meth abuse?
Delirium, tremor
What are psych effects of meth abuse?
Anxiety, paranoia, hallucinations, delusions
Can low dose psychostimulant improve performance?
Yes, but dosing and potency matter
