Ch 3 - synapses and synaptic transmission

Question 1

Local depolarization is an

Answer 1

excitatory postsynaptic potential

Question 2

Local hyperpolarization is an

Answer 2

inhibitory postsynaptic potential

Question 3

Presynaptic facilitation

Answer 3

more NT is released

Question 4

Presynaptic facilitation occurs when

Answer 4

a presynaptic axon releases a NT that slightly depolarizes the axon terminal of a second neuron, facilitating release of more NT into the cleft “priming effect”

Question 5

Presynaptic inhibition

Answer 5

less NT is released

Question 6

Presynaptic inhibition occurs when

Answer 6

an axon releases a NT that slightly hyperpolarizes the axonal region of a second neuron so less than neormal NT is released into the cleft

Question 7

NT act directly on

Answer 7

postsynaptic ion channels or activates proteins inside the postsynaptic neuron

Question 8

neuromodulators are released into

Answer 8

extracellular fluid and adjust the activity of many neurons

Question 9

Two types of NT

Answer 9

fast acting and slow acting
Fast - act directly (less than 1/1000 of a s)
Slow - act indirectly (1/10 of a sec to min)

Question 10

Neuromodulators effects last

Answer 10

minutes to days

Question 11

Specific fast acting NT and NM

Answer 11

Acetylcholine - usually +

Amino acids - glutamate Excit, GABA Inhib

Question 12

Specific slow acting NT and NM

Answer 12

Amines, Peptides, NO

Question 13

Receptors are typically named for

Answer 13

transmitter/modulator to which they bind

Question 14

Synaptic receptors act directly when

Answer 14

the receptor and ion channel make up a single functional unit

Question 15

Synaptic receptors act indirectly whe

Answer 15

using a cascade of intracellular molecules to activate ion channels or cause other changes within the postsynaptic neuton

Question 16

Postsynaptic receptors use three mechanisms to transduce signals

Answer 16

direct, indirectly, cascade

Question 17

Agonists are drugs that

Answer 17

bind to the receptor and mimic the effects of naturally occurring NTs

Question 18

Antagonists are drugs that

Answer 18

prevent the release of NTs or bind to the receptor and impede the effects of a naturally occuring transmitter

Question 19

Lambert Eaton Syndrome

Answer 19

disease in which antibodies destroy voltage gated Ca2+ channels in the presynaptic terminal

Question 20

Myasthenia gravis

Answer 20

disease in which antibodies attack and destroy nicotinic receptors on mm cells

Question 21

Channelopathy

Answer 21

disease that involves dysfunction of ion channels

cause some cases of epilepsy and migraine headaches

Question 22

What can serve as postsynaptic cell of a synapse

Answer 22

smooth muscle cell
hepatocyte
neuron in thalamus
mm cells of triceps

Question 23

How does botox produce paresis

Answer 23

inhibits the release of Ach from presynaptic terminal at neuromuscular junction

Question 24

Myesthenia gravis is an autoimmune disease that

Answer 24

destroys Ach receptors on postsynaptic membrane of mm and interferes with binding for repetitive mm contractions

Question 25

First step in sequence of actions in G protein receptr activity

Answer 25

NT bidns with receptor

Question 26

when an AP arrives at preasynaptic terminal

Answer 26

voltage gated Ca channels are activated and intracellular Ca stores are released

Question 27

the binding of Ach at neuromuscular junction results in

Answer 27

ESPS

Question 28

PTSD associated with

Answer 28

hyperactivity of NE system

Question 29

what meds used to treat myesthenia gravis

Answer 29

inhibit breakdown of Ach

Question 30

Antagonist drug acts by

Answer 30

preventing release of NT