A brief presentation on neurotransmitters and how they work.

1. Neurotransmitters
A&PI

2. Intro
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Neurotransmitters: chemical messengers
Neurotransmitters are essential to life, and need to be
balanced.
Can be affected by stress, poor diet, drugs, and genetic
predisposition.

3. How They Work
• Packaged into synaptic vesicles
and then released from the axon
terminal.
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Synapses: Sites of
communication.
Synaptic cleft: the space
between two neurons,
presynaptic & postsynaptic.
Action potential is the catalyst for
the release of neurotransmitters.

4. Types of Neurotransmitters
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More than 100 different kinds of neurotransmitters.
3 categories: amino acids, peptides, and monamine.
Excitatory neurotransmitters: those which create an excitatory
postsynaptic potential & fire more action potentials.
Inhibitory neurotransmitters: those which create an inhibitory
postsynaptic potential.
Oversimplification: many neurotransmitters have both receptors.

5. Excitatory and Inhibitory Synaptic
Potentials
https://www.youtube.com/watch?v=LT3VKAr4roo
(1:09)

6. Drug Effects & Neurotransmitters
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Agonistic Drugs:
enhance
neurotransmitter.
Antagonistic Drugs:
block/inhibit
neurotransmitter.

7. Acetylcholine
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First identified neurotransmitter, discovered in 1920 by
Otto Loewi.
Most widespread and most studied.
Muscle movements, memory, learning, regulation of
sleep cycles, conduction of pain.
Inadequate amount is found in people with Alzheimers.

8. Gamma-aminobutyric Acid (GABA)
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Amino acid group
Inhibitory neurotransmitter.
Impaired GABA receptors: anxiety disorders, panic attacks,
seizures, Parkinson’s.
Tranquilizing drugs increase or imitate the effects of GABA.
Oral supplementation of GABA is not proven effective, maybe due
to blood-brain barrier.
Drugs that increase GABA in the brain can be used to treat anxiety,

9. Glutamate
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Amino acid group
Common name: monosodium glutamate or MSG.
Found in all complex living organisms.
Most important excitatory neurotransmitter in the brain.
Involved in memory, cognition, and learning.
Impaired receptors can result in intellectual disabilities, alzheimer's,
amyotrophic lateral sclerosis, and lathyrism.

10. Serotonin
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Biogenic amine group
Inhibitory
Effects emotion, sleep, appetite, mood, and perception.
Inadequate levels can lead to depression, anger management
problems, OCD, and suicide.
Prozac prevents reuptake, warm milk does this as well.
Plays an important role in perception, LSD/hallucinogens block
serotonin receptor sites.

11. Norepinephrine
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Biogenic amine group
Involved in attention, concentration, consciousness,
control of body temperature, and pituitary gland
regulation.
Also a hormone in the body.
Underlies fight or flight response in brain with
epinephrine.
Agonistic drugs are used to enhance norepinephrine to

12. Dopamine
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Biogenic amine group
Inhibitory or excitatory
Pleasure and elation- both minor and major.
Plays a role in movement, attention, learning, and the brain’s
reward system.
Known for it’s importance in addiction- alcohol, opium, heroin,
cocaine, and nicotine all increase dopamine levels.
Inadequate levels can lead to ADHD, Parkinson’s.

13. References
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https://www.boundless.com/physiology/nervous-tissue/neurophysiology/types-of-neurotransmitters-by-function/
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http://thebrain.mcgill.ca/flash/i/i_01/i_01_m/i_01_m_ana/i_01_m_ana.html
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http://bioserv.fiu.edu/~walterm/b/addicitions/dopamine.htm
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http://webspace.ship.edu/cgboer/genpsyneurotransmitters.html