Pharmacological principles of addiction Flashcards
what does lethality mean?
how common is death through overdose?
what does DSMV mean?
Diagnostic and Statistical Manual of Mental Disorders five
what is the DSMV used for?
it is a criteria used to identify substance dependence
what is substance dependence?
a maladaptive pattern of substance use that leads to impairment or distress which is shown as tolerance, withdrawal etc.
what does the frontal cortex control?
Planning, Strategizing, Logic, Judgment
what does the corpus callosum control?
creativity and problem solving
what does the cerebellum control?
Coordinates muscles/ movement and thinking processes
what does the extended amygdala control?
Emotional responses: fear and anger
what does the hippocampus control?
Forms Memories and
Coordinates thinking processes
what does the dopamine pathway control?
- reward
- pleasure
- euphoria
- motor function
- decision making
what does the serotonin pathway control?
- mood
- memory
- sleep
- cognition
where are dopamine agonists administered into?
the nucleus accumbens
what is the mechanism of cocaine action?
- binds to dopamine transporter
- inhibits dopamine reuptake from synaptic cleft
- increasing dopamine activity
- causing hyperactivity of D1 and D2 receptors
what is the mechanism of amphetamine action?
- actively transported into cell by dopamine transporter
- dopamine actively removed from pre-synapse into synaptic cleft
- increasing dopamine concentration in the cleft so longer dopamine signalling
what happens to amphetamine in the synapse?
- it is transported into vesicles by vesicular transporters
- here it inhibits further transmitter packing
- so transmitter concentration in the cytoplasm increases causing it to diffuse into the extracellular space.
how do opiates work?
- bind to mu-opiate receptors in the GABAergic interneurones of the ventral tegmental area to inhibit GABAergic activity
- this therefore inhibits the inhibitory effect of GABA so there is an increase in dopamine neurone firing frequency
what effect does GABA usually have?
an inhibiting effect - it inhibits the firing of dopamine neurones
what is the mechanism of nicotine action?
- binds to nicotinergic acetylcholine receptors in the ventral tegmental area
- this has an excitatory effect
- it increases dopamine release
what is the mechanism of alcohol action?
- it potentiates GABA effects at the GABA receptor and inhibits the glutamate effects at the NMDA receptor
- this reduces GABAergic neurones
- this also enhances the excitatory effects of serotonin via 5HT receptors
what part of the brain is activated when drugs of abuse are abruptly ceased?
the thalamus
what does the corticotrophin releasing factor (CRF) system do?
mediates the affective and somatic symptoms of drug withdrawal
what effect do these neurotransmitters have when intoxicated with a drug:
a. dopamine
b. opioid peptides
c. serotonin
d. GABA
a. dopamine = euphoria
b. opioid = analgesia and relaxation
c. Serotonin = elevated mood
d. GABA = less anxious and panicky, more relaxed
what effect do these neurotransmitters have when experiencing withdrawal:
a. dopamine
b. serotonin
c. GABA
d. norepinephrine
e. glutamate
f. CRF
g. opioid peptides
a. dopamine = dysphoria
b. serotonin = dysphoria
c. GABA = anxiety and panic attacks
d. norepinephrine = stress
e. glutamate = hyperexcitability
f. CRF = stress
g. opioid peptides = increased pain
