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Fundamentals of Psychopharmacology
Matt Schalles UCSD Cognitive Science [email protected]
Drugs of Interest
l Psycho Stimulants l Caffeine l Opiates l Alcohol l Marijuana l Hallucinogens
l Dopamine l Adenosine l Endorphins l Everything l Endocannabiniods
- Serotonin like - Catecholamine like - dissociative
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Neurotransmitters of Interest
Amino Acids Glutamate (Glu) GABA
Biogenic Amines Quaternary Amines Acetylcholine (Ach) Monoamines Catecholamines Dopamine (DA) Norepinephrine (NE) Indolamines Serotonin (5-HT)
Neuropeptides Opioid Peptides Enkephalins Endorphins Dynorphins Endomorphins
(Others: lipids & soluble gases)
Stimulant Drugs l Psychomotor Stimulants
(Catecholamines) - Cocaine - Methylphenidate (ritalin) - Amphetamines (adderall)
l Cholinergic - Nicotine
l Adenosine - caffeine
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Psychomotor stimulant kinetics
l Absorption - Nasal membrane - stomach/intestinal - Lungs - Bloodstream
l Half Lives - Cocaine: 50-90 min - Methylphenidate: 3-4 hrs - Amphetamines: 6-8 hrs - Methamphetamine < 12 hr
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Cocaine/Methylphenidate site of action
Amphetamine Site of action
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Medical Uses
l Obesity l Narcolepsy l ADHD l Local anesthetics/ vasoconstrictors
Caffeine
l Adenosine Receptor - Ligand released by
astrocyte - Inhibits neurons - Competitive antagonist
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Opiates
l Opium - Morphine - Codeine
l Endogenous opioids - Endorphins - Endomorphins - Enkephalins - Dynorphins
Opiate Kinetics
l Absorption - stomach/intestines 20-30
min - Nasal membranes 5-8
min - Bloodstream 15-30 sec - Lungs 7-10 sec
l Metabolism - 3-5 hr half-life - Liver enzymes
l Excreted by kidneys
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Opioid Distribution
l 3 receptor types - Mu - Delta - Kappa
Site of Action
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Opioid Antagonists
l Naloxone - High mu receptor
affinity - Must be injected - Short action (15-30
min)
l Naltrexone - Similar binding profile - Orally active - 4 hr half-life - Induces withdrawal
Alcohol – the dirtiest of drugs
l Interacts with - Glutamate - GABA - Dopamine - Opiates - Serotonin - endocannabinoids
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Pharmacokinetics
l Absorption - Lipid soluble - Water soluble
l Metabolism - Zero order - First pass - Second pass - alcohol-dehydrogenase
l Eliminated through - Urine - Skin - Lungs - feces
Net Alcohol effects?
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EtOH Sites of Action
l GABA - Direct agonist - Indirect agonist
Cannabinoids
l CB1 receptor l Endocannabinoids
- 2-AG - anadamide
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Endocannabinoids
l Retrograde signaling l Negative feedback
mechanism l Depolarization
induced Suppression of Excitation
l DS inhibition
Hallucinogens
l Self Administration? l Psychedellics l Entheogens l Psychotomimetics
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Hallucinogens
l 3 Classes - Serotonin-like - Catecholamine-like - Dissociative /
Anesthetics
DMT l Synthesized by
mammals l Dedicated Receptors
in periphery
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Ayahuasca
Acetylcholine
l 1st Neurotransmitter discovered
l 2 Receptors - Nicotonic - Muscarinic
l Associated Functions - Memory - Attention - Muscles
l Acetylcholine esterase
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Compounds Affecting Ach
l Nicotine l Amanita Muscaria l Crotoxin l Latrotoxin l Botulism
