Psychopharmacology Flashcards
1 ) Which of the following represents a possible treatment for Parkinson’s disease?
A) neurosurgery to separate the corpus callosum
B) adminstration of MPTP
C) co-administration of amphetamine and meperidine
D) administration of L-DOPA
E) None of the above are correct.
D) administration of L-DOPA
2 ) Which of the following is a characteristic of a drug?
A) effective only at high doses
B) can include essential nutrients
C) must be an endogenous chemical
D) can be abused or misused by humans
E) an exogenous chemical
E) an exogenous chemical
3 ) Drugs that block or inhibit the postsynaptic receptor effects are termed
A) agonists.
B) ligands.
C) synergists.
D) antagonists.
E) pheromones.
D) antagonists.
4 ) Which pair of transmitters are most involved in synaptic neurotransmission in the brain?
A) glutamate; acetylcholine
B) GABA; glycine
C) glutamate; GABA
D) glycine; acetylcholine
E) acetylcholine; dopamine
C) glutamate; GABA
5) Match up the transmitter substance below with the appropriate behavioral role or action of that transmitter.
A) acetylcholine; facilitation of learning
B) dopamine; suppresses certain species-typical behaviors
C) norepinephrine; facilitation of learning
D) serotonin; increases vigilance
E) GABA; generally activates voluntary movements
A) acetylcholine; facilitation of learning
6) Parkinson’s disease involves degeneration of neurons within the ________ DA system.
A) nigrostriatal
B) mesocortical
C) hypothalamocortical
D) mesolimbic
E) retinal-suprachiasmatic
What are the 2 types of receptors?
ionotropic and metabotropic
Ionotropic
site for neurotransmitters to bind is on neuron
Faster and short lived
Metabotropic
receptor site is at another location separate from the channel
Operates a G protein which activated the channel
Long and slow
What does it take to be a neurotransmitter?
Exists pre-synaptically.
Released in response to action potential.
- Ca enters cell , vesicles bind with presynaptic membrane
Application at synapse produces response.
- post-synaptic membrane has receptors which bind with neurotransmitter and has effect
- Can be EPSP or IPSP
Blocking release stops synaptic function.
Psychopharmacology
The study of the effects of drugs on the nervous system and on behavior.
How are drugs influencing our nervous system and in turn how does that influence our behavior
Drugs we take, drugs naturally existing in brain,
Drug effects
The changes a drug produces in an animal’s physiological processes and behavior.
What is a ‘drug’?
a very vague term.
all ingested substances alter bodily function.
- We don’t say bananas are drugs cause when we eat them they alter our bodily functions
‘drug’ is reserved for things that have pronounced effects when ingested in small quantities but has a significant effect on our behavior and physiological behvaiour
Tiny pills or plants
Sites of Action
The locations at which drugs interact with cells of the body, thus affecting some biochemical processes of these cells
What can drugs be classified as?
Agonist or Antagonist
THESE ARE NOT LIKE IPSP AND EPSP
Neurotransmitter determines if exicitory or inhibitory
Agonist
A drug that facilitates the effects of a particular neurotransmitter on the postsynaptic cell.
Increase the chances of whatever effect
If neurotransmitter usually has inhibitory effect the agonist makes it easier for that effect to happen
Agonist drug binds at same sites as neurotransmitter and produces same effects and this will free up neurotransmitter to bind at more sites so you have enhanced cellular activity
Antagonist
A drug that opposes or inhibits the effects of a particular neurotransmitter on the postsynaptic cell.
Makes it harder for effect
- plugging up receptor sites and not opening channels causing the natural neurotransmitter to not bind at those sites so your blocking neural activity
List some ways that drugs can agonize
- precursor to neurotransmitter
In parkinsons your cells arent produing enough dopamine but you cant give a person a dopamine pill because it won’t cross the blood brain barrier instead you give L-Dopa which is able to cross blodd brain barrier and turn into dopamine
L-Dopa is providing building blocks so that the brain can get more dopamine
stimulate release
- More neurotransmitter you have released into the synapse the more likely the effect will happen on post synaptic membrane
- Ex- emphadimine
receptor binding
- Imitate a neurotransmitter and bind at the channel….
block auto receptors
- Auto receptors are metabotropic receptors at pre synaptic membrane
- If these are blocked the cell keeps on pumping neurotransmitter
- More neurotransmitter released more in synapse more effect
inhibition of reuptake
- Ex if we add cocaine we block the reuptake meaning the neurotransmitter can keep operating at the synapse
inhibition of deactivation
List Ways that drugs can antagonize
prevent synthesis
- Stop conversion of precursor into neurotransmitter meaning less is avaible preventing the neurotransmitter from doing its job
prevents storage
- Interfere with storage then that reduces amount of neurotransmitter to be released
block release
receptor blocker
- Imitate neurotransmitter bind at site but not activate
stimulates auto receptors
- Reuptake neurotransmitter making it harder for it to have effect on post synaptic membrane
Direct agonist
Binds at same site neurotransmitter would- competitive binding
- keeps channels open
Direct antagonist
binds at the same site as the neurotransmitter but keeps the ion channel close
Indirect antagonist
drug keeps ion channels closed
Binds at different site.
- noncompetitive binding
Indirect agonist
drug keeps ion channels open
- noncompetiive binding
List the four major neurotransmitter systems
Acetylcholine- thought to play a role in memory, part of Alzheimer disease
Dopamine- movement, Parkinson’s disease, to much l- dopa to much dopamine= schizophrenic symptoms
- Substantia nigra
Norepinephrine- emotional regulatory, to little= depression to much= maniac
Serotonin- walking cycles, obsessive compulsive disorder
Amines
Modulatory effect on systems
Monoamines
catecholamines (dopamine, norepinephrine)
indoleamines (serotonin)
Quaternary amines
Acetylcholine
Information transmitters
amino acids (glutamate, GABA)
Learning, info transfer
Acetylcholine
muscular movement
high during REM sleep- rapid eye movements
- learning
- Memories
- Forgettting
Cholinergic pathways in the brain - basal forebrain, dorsolateral pons.
Dopamine
related to movement
metabotropic receptors
Amphetamines alter dopamine uptake and produce schizophrenic-like delusions.
can see similar effects with cocaine use.
Parkinson’s disease – degeneration of the nigrostriatial dopamine system.
Norepinephrine
These are modulatory effects so they aren’t responsible for appetite but changes in the drug level can make you hungry or full- modifies things
- increase in vigilance
- attention
- sexual behavior
- appetite
Noradrenergic pathways in the brain - locus coeruleus
Serotonin
regulation of mood
control of eating, sleeping and arousal
regulation of pain
dreaming
Serotonergic pathways in the brain – raphe nuclei
Glutamate
the primary excitatory neurotransmitter
GABA
the primary inhibitory neurotransmitter
Amino acids:
The workhorses of the neurotransmitter family
Other neurotransmitters have more of a modulatory effect – rather than an information transmitting effect
Information that is learned and remembered is transmitted by neurons secreting glutamate and GABA
The glutamate receptor
Activation of NMDA receptor can cause entry of calcium and changes in the numbers of AMPA receptors – a mechanism for learning? Building blocks of a newly formed memory?
The GABA receptor
inhibitory synapses
necessary for brain stability
Epilepsy - an abnormality in this process
Barbiturates
gaba agonists
- anxiety drugs
- sleep medication
- seizure treatments
Peptides
produced in minute quantities.
often substances that are also found in areas of body other than brain (vasoactive intestinal polypeptide).
tremendously potent and long-acting (neuromodulatory).
Opiates
The opiate story
Opiates have been used for centuries to relieve pain.
It wasn’t until 1975 that we discovered endogenous (produced from within, naturally occuring) opioids.
Like runners high where they feel better after run
several varieties of receptors.
Incentive sensitization model
the wanting and liking theory.
wanting – equivalent to craving a drug
liking – pleasure from drug taking
repeated use:
tolerance for liking
wanting becomes sensitized
Acetylcholine how it’s made
Acetyl-CoA & Choline mix & ChAT transfers acetate ion from acetyl-CoA to choline - all together form CoA & ACh
Which drugs are the most addictive?
fast-acting drugs are most addictive
e.g., cocaine, heroin
Why are slow-acting drugs addictive?
the effect of the drug is paired with the memory of taking the drug
e.g. alcohol- I was nervous before I went to a party and took shots and was amazing so next time you think you need to drink next time or you have a presentation and know alcohol calms you down so you drink
Do animals get addicted to drugs?
difficult to addict animals to slow-acting drugs.
Monkey in Caribbean have become addicted to alcohol
Liking in alcohol is determined by our genes
Most effective:
stimulus —-> immediate response
hence the high addictiveness of fast-acting drugs
preference for heroin over morphine
Heroine was developed to get soldiers off morphine
Neural Mechanism
addictive drugs (and other reinforcers) cause the release of DA in the nucleus accumbens.
What are the 2 types of actions for neural mechanism?
two types of actions:
dopamine agonist
IMITATING DOPAMINE SITE SO YOU AHVE MORE DOPAMINE AVAILABLE
reuptake inhibitor
Like what cocaine does
Schizophrenia
Affects about 1/100 people.
Begins in 20’s.
Often triggered by stress and illness but there’s also a genetic predisposition.
Amanda bynes
Symptoms of schizophrenia
Positive symptoms
- hallucinations, delusions, paranoia
Negative symptoms
- lack of emotion, energy, directedness
The dopamine theory of schizophrenia
Dopamine antagonist
Over activity in the mesolimbic dopamine pathway is thought to mediate the positive symptoms of schizophrenia such as delusions and hallucinations (Figure 1).
More recently, under activity in the mesocortical dopamine pathway has been hypothesized to be the mediator of negative symptoms of schizophrenia (Figure 2).
Beyond dopamine
New generation antipsychotics affect serotonin as well
Glutamate agonists can help with negative symptoms.
- But they can cause seizures.
- Glycine (amino acid) agonists are usually given that facilitate glutamate but don’t have the dangerous side-effects.
Schizophrenia likely affects a host of systems perhaps by disturbing a fundamental balance among neurotransmitters
Alzheimer’s Disease
First described by Alois Alzheimer in 1907.
Course of disease:
initially, some memory loss (new memories and disorientation).
relentlessly progressive until one loses identity.
Neuropathology in Alzheimer’s disease
amyloid plaques neurofibrillary tangles
What are treatments of AD?
- ‘Cognitive enhancers’
- Acetylcholinesterase inhibitors to offset loss of cholinergic neurons.
- stops ACE from destroying synaptic ACH - NMDA receptor antagonists
- Cells damaged by AD release a large amount of glutamate, which over-excites NMDA receptors, which in turn speed up cell damage. Partially blocking NMDA receptors prevents this destructive chain.
i
Nucleus basalis of Meynert – cell loss seen in AD
