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• Upload 9.081 Neurotransmitters and Drugs
• To eBackpack

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Neurotransmitters

• What is a neurotransmitter?
• A chemical secreted by an axon.
• Watch video
• Excitatory neurotransmitters
• - lead to changes that generate an action
  potential in the postsynaptic neuron
• Inhibitory neurotransmitters
• - tend to block the changes that cause an action
  potential to be generated in a postsynaptic
  neuron

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• Watch an animation on neurotransmitters
• What ion causes the release of neurotransmitters
  from the axon terminal?
• Calcium

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• What ion channel will be opened during excitatory
  response?
• Sodium (ions will rush into the postsynaptic
  neuron causing an action potential)
• What ion channel will be opened during inhibitory
  response?
• Chlorine (ions will rush into the postsynaptic
  neuron making the inside of the cell more
  negative therefore no action potential)

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• What happens if both excitatory and inhibitory
  signals are sent?
• The impulses are summated and the greatest type
  is carried out.
• ALL OR NOTHING RESPONSE
• What happens to the neurotransmitters after they
  have fused with the postsynaptic receptor?
• Broken down by enzymes or they reenter the
  presynaptic axon terminal

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Excitatory neurotransmitters

• Acetylcholine
• Glutamate
• Epinephrine
• Serotonin

• Sleepiness, mood
• Activates muscles
• Learning and memory
• Also called adrenaline, keeps you alert and
  mentally focused

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Inhibitory Neurotransmitters

• Endorphins
• Dopamine
• GABA

• Calms the brain, controls anxiety
• Reduce pain and increase pleasure
• Motivation and pleasure, known for its role in
  addiction

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• Glutamate The most common and most potent
  excitatory neurotransmitter in the CNS
• GABA and glycine The major inhibitory
  neurotransmitters in the CNS.
• Acetylcholine and norepinephrine are the most
  important neurotransmitters in the PNS.

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Effect of drugs on neurotransmission

• When neurons do not communicate normally, the
  brain does not function normally either.
• Cocaine
• How does cocaine affect neurotransmission?
• Why are many drugs addictive?
• -Tolerance
• -Withdrawal
• Mouse Party Interactive On-line Activity
• How does marijuana affect neurotransmission?
• Summary- Rats on Drugs

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Determine what happens when 2 drugs are mixed

• Caffeine (disrupts adenosine)
• Alcohol (disrupts GABA)
• Link to example
• Open Effect of Drugs on Neurotransmission
• Complete by 7pm tonight