Neurons and Drugs Flashcards
Hormone vs Nervous system
hormone system : stress in response to the environment; long term development
nervous system : short term development; immediate response
Neuron
single cell
Nerve
bundle of neurons
Organization and function of nervous system (6)
soma : cell body
dendrites : receive signal from external stimulation or other neurons
nucleus : stores information
axon : information passes through
myelin sheath : insulates area, protect the electric signal
terminal button : keep message from beng dissipated
Process of transmitting information
- dendrite receives signal from external stimulation
- action potential
- delivers information through synapse
Action potential process
- resting state (sodium and potassium close)
- depolarizing state (sodium open, rush in)
- repolarizing state (potassium open (sodium close), rush out)
- undershoot
- return to resting state (sodium and potassium open; sodium out, potassium in)
Synaptic process
- action potential travels down axon and reach terminal button
- calcium channels open, calcium rush in
- vesicles with neurotransmitters binds with terminal button membrane
- neurotransmitters dumped into synaptic clef
- some neurotransmitter binds with receptor and opens channel
- neurotransmitters floats away from the receptor
- reuptake / enzymatic breakdown of neurotransmitters
Myelin sheath + relation to development and disease
- myelin sheath : fatty substance surrounding the axon to insulate the axon and protect electric signal
- when babies are still developing or because of disease, the myelin sheath is not developed –> information is lost when it is moving through the axon –> body not responding properly
Neurotransmitter
acetylcholine : movement, action
dopamine : pleasure
serotonin : emotion
Drugs influence on stuff at the synapse
- block protein that help defuse vessels that hold the the neurotransmitter with the membrane to dump the neurotransmitter
- binds to reuptake protein in pre-synaptic membrane (blocking reuptake of neurotransmitters, resulting in multiple his at the post synaptic cell)
- influence how enzyme breaks down neurotransmitter in the synaptic clef
Examples of drugs and how the function
block protein from fusing vesicle with terminal button membrane : botox
bind to receptor : LSD
mimic neurotransmitters : Oxycontin
blinds to reuptake : Prozac, Ecstacy, Adderall
botox :
- block protein from fusing the vesicles with terminal button membrane
- prevent release of acetylcholine = paralyze muscle = prevent wrinkles
Crystal meth :
- stimulate dopamine and serotonin release
LSD :
- binds to serotonin receptors
- increase receptor’s sensitivity
Oxycontin :
- mimic neurotransmitters in pain neurons
- block feeling of pain
Prozac :
- binds to reuptake
Ecstacy :
- increase serotonin production
- blocks serotonin reuptake
Adderall :
- increase release of adrenaline and dopamine
- blocks reuptake of adrenaline, dopamine, and serotonin
Adenosine + Caffeine
- adenosine : cell exhaust, by-product of cellular metabolism
- adenosine binds to receptor, allows sodium to enter, signal us to sleep when there is too much buildup
- caffeine binds to the receptor but does not open the channels
- caffeine does not allow for more adenosine to open more channels and also remove adenosine away from receptor (no action potential telling us to sleep)
Alcohol (process + flushing)
Process
- alcohol dehydrogenase (ethnol –> acetaldehyde)
- aldehyde dehydrogenase (acetaldahyde –> acetic acid)
Flushing
- some people have genes that produce an inactive form of aldehyde dehydrogenase
- when these people dink alcohol, they increase in acetaldehyde level and make people feel unpleasant
- 2 copies = fast flushing
- 1 copy = slow flushing
- could be a protective gene discouraging our body from drinking
