Lecture 7 (Neurotransmitters, Drugs, Neurotoxins)

Question 1

How many known neurotransmitters are there?

Answer 1

Around 100

Question 2

Name 6 neurotransmitters

Answer 2

• Acetylcholine (Ach)
• Glutamate (major excitatory neurotransmitter int eh vertebrate CNS)
• Gamma aminobutyric acid (GABA) (inhibitory neurotransmitter)
• Dopamine
• Serotonin
• Epinephrine

Question 3

What is the main function of Acetylcholine (ACh)?

Answer 3

Crosses the synapse between a motor neuron and a muscle fiber.
Binds to a receptor in a postsynaptic membrane
Stimulates muscle contraction

Question 4

What’s the main function of Dopamine as a neurotransmitter?

Answer 4

Involved in emotional responses, addictive behaviours and pleasurable experiences

Question 5

What’s the main function of serotonin as a neurotransmitter?

Answer 5

Involved in the sensory perception, temperature regulation, control of mood and sleep

Question 6

What’s the main function of epinephrine (adrenaline) as a neurotransmitter?

Answer 6

Responsible for the “fight or flight” response

Question 7

Drugs can affect neurotransmitters in various ways. What’s the main function of valium as a drug?

Answer 7

Anti-anxiety drug that enhances the action of GABA

Question 8

Drugs can affect neurotransmitters in various ways. What’s the main function of Prozac as a drug?

Answer 8

Anti-depression medication that acts as serotonin reuptake inhibitor (keep serotonin in cleft longer)

Question 9

Drugs can affect neurotransmitters in various ways. What’s the main function of Cocaine as a drug?

Answer 9

Produces euphoria and pleasure by blocking reuptake of dopamine

Question 10

Drugs can affect neurotransmitters in various ways. What’s the main function of MDMA as a drug?

Answer 10

Also ecstasy, causes release of serotonin, dopamine and norepinephrine

Question 11

Define drug addiction

Answer 11

• Prolonged exposures to a stimulus may cause cells to lose the ability to respond to it
• Process called habituation
• The cell decreases the number of receptors because there is an abundance of neurotransmitters

Question 12

Define Neurotoxins

Answer 12

Natural or synthetic compounds that interact with ion channels. Then APs can be blocked.

Question 13

Give an example of where tetrodotoxin is found?

Answer 13

Puffer fish: blocks Na+ voltage-gated channels (No depolarization)
Results in paralysis and death

Question 14

Give an example of where dendrotoxin is found?

Answer 14

Black Mamba snake: blocks voltage-gated K+ channels (No repolarization)
Results in paralysis and death