Neurotransmitters

Question 1

How do receptor and postsynaptic potentials work?

Answer 1

• both are graded changes of membrane excitability that decay away from the site of stimulation
• the membrane potential must be at some threshold level at the critical point on the axon that contains the voltage-gated ion channels
• if threshold depolarization is not achieved at this point, no AP is initiated

Question 2

What are the two possible mechanisms of neurotransmitters influencing the postsynaptic cell

Answer 2

• Ionotropic

- Metabotropic

Question 3

Which type of neurotransmitter receptor is localized with actual ion channels?

Answer 3

ionotropic

Question 4

Which type of neurotransmitter receptor is located at some point on the membrane but activate an ion channel some distance away via a second messenger system (g-protein-coupled receptors)?

Answer 4

metabotropic

Question 5

What are 3 fast, excitatory neurotransmitters?

Answer 5

• ACh
• glutamate
• epinephrine
• -> use ionotropic receptors and sometimes metabotropic receptors

Question 6

What are the 2 fast, inhibitory neurotransmitters?

Answer 6

• GABA
• glycine
• -> use ionotropic receptors and sometimes metabotropic receptors

Question 7

Enkephalin, calcium binding protein, substance P are all found in what class of compound?

Answer 7

Neuropeptides - complex AA peptides

Question 8

Neuropeptides use what kind of receptor?

Answer 8

metabotropic receptors

Question 9

nitric oxide, eiconasoids (prostaglandins, cannabinoids) are all found in what class of compound?

Answer 9

Non-traditional neurotransmitters

Question 10

What kind of neurotransmitters can affect adjacent cells?

Answer 10

Non-traditional neurotransmitters

Question 11

Neurotransmitters are co-localized with what in axonal terminals?

Answer 11

neuropeptides

Question 12

Any efferent information coming out of the cortex uses what neurotransmitter?

Answer 12

glutamate

Question 13

Function of co-localization of neurotransmitters with neuropeptides?

Answer 13

the peptide acts as a neuromodulator by modifying the activity of the cell during neurotransmission, as well as prolonging membrane activity

Question 14

What determines the action (excitatory or inhibitory) of the neurotransmitter?

Answer 14

post-synaptic receptor –> i.e. what kind of ion channel is the receptor located on?

Question 15

What type of ion channel are nicotinic (acetylcholine) receptors located on?

Answer 15

Na+ channels

Question 16

What type of ion channel are GABA and glycine receptors located on?

Answer 16

Cl- channels

Question 17

Fast neurotransmitters act on ionotropic receptors, as well as what other receptor type?

Answer 17

metabotropic receptors

Question 18

Catecholamines (norepinephrine, epinephrine, dopamine) act only through what type of receptor?

Answer 18

metabotropic receptors

Question 19

What type of ion channels are glutamate receptors located on?

Answer 19

Na+ and K+ channels and sometimes small amounts of Ca++ channels

Question 20

GABA has been found to be co-localized with what neuropeptide (specific to different structures/regions of the brain)?

Answer 20

calcium binding protein