Neurotransmission Flashcards

1
Q

Define neurotransmission:

A

transmission of nerve impulses across a synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define neuroconduction:

A

movement of nerve impulses down neurons; also called propogation of nerve impulses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the term of an axon meeting a dendrite

A

axodendritic synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the term of an axon meeting a soma

A

axosomatic synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the term of an axon meeting a axon hillock

A

axoaxonic synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

In axons, where is the wave of depol iniated?

A

axon hilock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define axon hillock

A

a smol area in cell where axon meets soma, this area is the most sensitive to electrical stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which area is the most sensitive to electrical stimulation?

A

axon hillock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Only a short section of axon is _____ at any one time, but AP still moves alon axon

A

depolarizing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why doesnt reverse conduction occur?

A

area behind depol membrane is in refractory period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the three reasons for refractory period?

A

asures transmission is one way, APs are separate events, and allows cells to recover to the resting state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is AP transmission ensured to be one way

A

K+ channels open behind signal so it can only go one way bc of open voltage gates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why do AP need to be separate events

A

so coding of message is possible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What contributes to strength of stimulus

A

AP frequency and NOT amplitude bc all APs are the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what would happen to neurons in terms of recovery if refractory period was removed?

A

neurons might run down due to loss of ions/energy shortages due to large use of energy to shift ions back to re-establish RMP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Does wave of depol always occur?

A

nope, could be saltatory conduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

where does wave of depol occur?

A

unmyelinated neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

in saltatory conduction, AP jumps btw what?

A

node de ranvier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Does more square meter of axon have to depol in salt conduction or wave of depol?

A

wave of depol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Mylein speeds up process how?

A

only a short section of axon has to depol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Mylinated speed vs unmyelinated?

A

150ms vs 50 ms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is myelin

A

fatty insulation for neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is an alternative to myelin that speeds up AP?

A

thick axons sped up process bc less resistance to current flow (i.e. ion movement) with a larger membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Myelinated axons are used for what?

A

skeletal muscle and SOMATIC pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is a somatic pain

A

sharp and quick

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what happens in demyelinated disease

A

message is unpredicrable, cant control muscle, dont get normal sensory msg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the patholgy of unmyelinated disease?

A

als

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Depole of one node means the node behind it is in which period?

A

refractatory period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the two ways of communicating btw neurons?

A

electrical and chemical synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Define electrical synapse

A

The electrical signal is transmitted across synapse by inducing ionic movement in adjact cell, thus allowing neurotransmission ; voltage change in one cell causes voltage change in adjacent cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Where can you find electrical synapses?

A

myocardium and uterus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Why are electrical synapses useful?

A

allows cells to stay synchronized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what muscle uses electrical synapse?

A

smooth muscle, i.e GI tract, heart, uterus, bronchioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are gap junctions?

A

a hole btw 2 adjacent cells allowing electrical synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What flows through gap junction?

A

anything can flow through!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What flows through gap junction and causes depolarization?

A

ions flow through causing depol in postsynaptic membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What channels are present at axon terminal?

A

voltage-sensitive CA channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What does CA influx stimulate?

A

vesicles containing NT to fuse with presynaptic membrane and release contents into synaptic cleft via exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

How do NT travel across synapse?

A

down concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

NT-receptor is bound to what channel?

A

ligand gated sodium channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

When does sodium channel close in respect to NT?

A

when NT broken down by enzymes and taken back to presynaptic neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

_______ _____ can occur from one or more neurons

A

temporal summation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

define post synaptic potential

A

the voltage change (all the graded potentials) occuring in post synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

EPSP involves which channel opening? Causes what to voltage?

A

sodium channels open, voltage increases, cell is brough closer to threshold

45
Q

IPSP involves which channel opening? Causes what to voltage?

A

voltage decreases, potassium channels open, brings cell further from threshold

46
Q

Define NT

A

a substance that transmits signals across the synapse

47
Q

Where can NT be released from?

A

presynaptic and postsynaptic membrane

48
Q

What do NT do?

A

change membrane voltage (i.e. generate IPSP or EPSP_ ) and or can alter cell function

49
Q

What do all biogenic amines contain?

A

the amino functional gorup R-NH2

50
Q

What are the four types of biogenic amines

A

acetylcholine, catecholamine, serotonin,histamine

51
Q

Amino acids are found where?

A

only in CNS

52
Q

Acetylcholine is found where?

A

at all ANS ganglia and neuromuscular junctions

53
Q

What does AcH do?

A

stimulates striated muscle to move

54
Q

Which muscle type does ACH innervate?

A

striated muscle

55
Q

which biogenic amine isnt always considered a biogenic amine?

A

ach

56
Q

Catecholamines are defined by what?

A

catchol and amino group

57
Q

What are three catecholamines?

A

dopamine, NR and E

58
Q

NE is released into ___ and released at ___ from ______

A

released into blood from adrenals and released at synapses

59
Q

Epinephrine is part of which NS?

A

sympathetic

60
Q

Epinephrine is a pre or post ganglionic NT?

A

post!

61
Q

Serotonin is associated with what?

A

sleep, dreaming, nausea, vomitting, affective tone (mood)

62
Q

low aaffective tone?

A

depressed

63
Q

High affective tone?

A

wound up

64
Q

LSD occupied which receptors and causes what?

A

occupies serotononin receptor and causes hallucinogens

65
Q

Histamine is important to which NS?

A

CNS

66
Q

which biogenic amine is associated with allergic response?

A

histamine

67
Q

What are the four amino acids?

A

glutamine asparate GABA and glycine

68
Q

which amino acids are excitatory

A

glutamate, asparate

69
Q

Which amino acids are inhibitory?

A

gaba and glycine

70
Q

Give three examples of peptides

A

substance P, oxytocin, enkephalins

71
Q

What does substance P do?

A

pain NT

72
Q

what does oxytocin do?

A

stimulate uterine contraction and milk expression

73
Q

What does enkephalins do?

A

pain control NT that acts on opiate receptors

74
Q

What is the catcholamine synthesis

A

tyrsosine -> L-dopa -> dopamine -> NE -> E

75
Q

Oxygen enters at which step in catecohaline synthesis?

A

tyrosine -> L-dopa

76
Q

CO2 enters at which step in catecohaline synthesis?

A

L-dopa -> dopamine

77
Q

Which substance interferse with enxyme that leads to L-dopa synthesis?

A

alpha-methyltyrosine

78
Q

What does alpha methyltyrosine do?

A

interferse with enxyme that leads to L-dopa synthesis; therefore no DOP, NE, E

79
Q

How does alpha methyltyrosine impact NS?

A

no sympathetic actions

80
Q

What are the symptoms of alpha methyltyrosine?

A

high blood pressure, high heart rate, i.e. frightened

81
Q

What do you give parkinsons patients?

A

L-dopa to help enhance dopamine production

82
Q

Substantia nigra is malfunctioning, what substance do you give them?

A

L-dopa

83
Q

Too much L-dopa causes what?

A

manic; too much NE and E

84
Q

How are NT removed?

A

inactivation and reuptake

85
Q

What enzyme inactivates epinephrine, NE, and dop?

A

MAO (monoamine oxidase)

86
Q

What does mao do to E?

A

converts it to aldehyde

87
Q

If you hold the mao what happens?

A

NE and E dont break down, theyre symp dominant, so less depression

88
Q

Which NT are sympathetically dominant?

A

NE and E

89
Q

What is the dominant NT removal method?

A

reuptake , especially for catecholamines

90
Q

Reuptake is what type of transport?

A

active transport

91
Q

SSRIS stands for what?

A

selective serotonin reuptake inhibitors

92
Q

Example of SSRIS?

A

fluoxetine

93
Q

What can be used as an anti depressant?

A

fluoxetine, bc inhibits reuptake of serotinin, and increased serotinin leads to increased affective tone

94
Q

Fluoxetine is also called?

A

prozac

95
Q

Example of norepinephrine reuptake inhbitors?

A

buproprion blocks reuptake of NE and E

96
Q

wellbutrin blocks reuptake of what?

A

NE and E

97
Q

buproprion blocks reuptake of what

A

Ne and E

98
Q

fluozetine blocks reuptake of what

A

serotinin

99
Q

prozac blocks reuptake of what

A

serotinin

100
Q

cocain blocks reuptake of what

A

NE and E; therefore causing manic feeling due to high sympathetic levels

101
Q

Cocain gives you what feeling?

A

flight, fright, fight

102
Q

Tranycylpromine blocks reuptake of what

A

NE

103
Q

Tranycylpromine is considered a ______ ____

A

tricyclic antidepressant

104
Q

Which substances block reuptake of NE and E?

A

buproprion, wellbutrin, cocain, tranycylpromine (only NE)

105
Q

Nerve gases do what?

A

inhibit breakdown of ACH

106
Q

what symptoms do nerve gases cause?

A

continous Ach stimulaition, muscle fatigue, death

107
Q

Antidote for nerve hases?

A

block ach receptor with atropine

108
Q

What is tetrodotoxin?

A

sodium channel blocker