drugs Flashcards
cocaines effect
- stimulant effect on brains CNS, especially on the neurons of the brains main reward system
how does cocaine have the effect on cns
- it alters synaptic transmission involving different neurotransmitters
which neurotransmitters does cocaine effect
noradrenaline
serotonin
acetylcholine
dopamine
which neurotransmitter does cocaine effect the most
dopamine
cocaine increased release of dopamine
what does dopamine do
- a sense of pleasure
where is dopamine released
reward centers of brain
what does cocaine block the trip take of
dopamine
how does cocaine block the trip take of dopamine
- by binding with dopamine transporter molecules on the terminal buttons in the presynaptic neurons which are responsible for recycling dopamine back into the neuron that produced it
because cocaine blocks reuptake of dopamine what happens
- the synapse is flooded with surpless quantities of dopamine all available for binding with postsynaptic receptors
- this is why cocaine gives us a euphoric high
long term effects of cocaine
- after repeated use dopamine receptors become downregulated
- this explains withdrawal and craving for the drug and higher doses needed to get the same effects
downregulated
- fewer receipts are active, some are damaged and shut down so the quantity of dopamine produced declines
heroin effects
- depressant effects on cns slowing down its activity
- including activity of neuroses involved in pain = why it’s an analgesic
how is heroin taken
usually injected intravenously
once heroin reaches the brain how is it processed
most of it has processed into morphine
what does the morphine from the heroin bind do when it reaches the brain
- a specific opioid receptor at the synapse found in the cerebral cortex, limbic system and hypothalamus
why do these specific opioid receptors exist in the brain for heroin and morphine
the cns has its own opioid system
when heroin binds to the receptors of the natural opioid system what happens
endorphins and enkephalins are produced by the body as natural painkillers
what type of drug is heroin
agonist
why is heroin an agonist drug
it mimics the action of another natural biochemical
long term effects of heroin
- downregulation on neural transmission
- opioid receptors on postsynaptic neurones are constantly binding with morphine molecules which desensitisises them to effects of the drug
ecstasy
-cns stimulant that blocks reuptake of serotonin at the synapse
- causes neurons to increase their output of serotonin initially
what does the activity of ecstasy or mdma do ?
create a double whammy of serotonin enhancement
- greater quantities are made available in the synapse for binding to post synaptic receptors