Lecture 4 - Autonomic Nervous System Flashcards
1
Q
Why study the autonomic nervous system?
A
- homeostasis (tightly controlled internal environment)
- drug actions
- drug side effects
2
Q
Explain the nervous system tree
A
NS:
- CNS
- PNS
PNS:
- motor nerves
- sensory nerves
Motor nerves:
- autonomic (movement of smooth muscles ex. intestines)
- somatic (movement of skeletal muscles)
Autonomic NS:
- parasympathetic
- enteric
- sympathetic
*we will be focusing on parasympathetic/sympathetic!!
3
Q
sensory nerves are known as ??
A
afferent nerves (info from the periphery flows into CNS)
4
Q
motor nerves are known as ???
A
efferent (info flows from the CNS to the periphery)
-results in peripheral change (motor)
5
Q
somatic nervous system is ___ controlled
A
consciously
6
Q
PNS and SNS are both _____ systems
A
efferent (motor)
“visceromotor”
7
Q
PNS and SNS involve regulation of our ____ environment
A
internal
out of our control
8
Q
PNS and SNS both involve _ neutrons that synapse in a peripheral ganglion
A
2
9
Q
What 3 things do the PNS and SNS innervate?
A
- glands
- smooth muscle
- cardiac muscle
10
Q
in daily life - vast majority = ?
A
parasympathetic
you’re relaxed, digesting, not expending energy
11
Q
ergo tropic = ?
A
energy expenditure
*this is part of SNS
12
Q
fight or flight = ?
A
sympathetic
13
Q
rest and digest = ?
A
parasympathetic
14
Q
trophotropic = ?
A
leading to growth
(energy storage)
*this is part of PNS
15
Q
Where is SNS innervated?
A
thoracic lumbar segments
16
Q
Where is PNS innervated?
A
cranial and sacral segments
17
Q
T or F:
SNS - can pick and choose which organ to activate
A
False
PNS - can pick and choose which organ to activate
SNS - usually has to affect the whole body
18
Q
If you’re in danger of dying or running from a gorilla (RIP Harambe) or crap like that = ___ activated
A
SNS
19
Q
If you’re just chillin (like a villain) = ___ activated
A
PNS
20
Q
SNS has ___ preganglionic axon and ___ postganglionic axon
A
short preganglionic axon
long postganglionic axon
21
Q
PNS has ___ preganglionic axon and ___ postganglionic axon
A
long preganglionic axon
short postganglionic axon
i.e. it is right near it’s target so it can pick and choose organs ??
22
Q
All preganglionics release ___ and are ________
A
Ach
excitatory (+)
23
Q
Symp postganglionics release ___ and are ??
A
NE
excitatory (+) or inhibitory (-)
24
Q
Parasymp postganglionics release ___ and are ??
A
Ach
excitatory (+) or inhibitory (-)
25
PNS targets ?
organs of head, neck, trunk, & external genitalia
26
SNS targets ?
- organs of head, neck, trunk & external genitalia
- adrenal medulla
- sweat glands in skin
- arrector muscles of hair
- all smooth vascular smooth muscle
27
SNS is distributed where?
essentially all tissues (because of vascular smooth muscle)
28
PNS is distributed where?
only head, neck, truck, and external genitalia
-never reaches limbs or body wall (except for external genitalia)
29
____ is catabolic (expend energy)
SNS
30
____ is anabolic (save energy)
PNS
31
T or F: you can have dual innervation of many organs and have it act like a brake and accelerator to provide more control
TRUE
32
What would SNS do to:
| heart
increase heart rate
| increase BP
33
What would SNS do to:
| blood vessels
blood vessels constrict and allow more blood to move to to the muscles
34
What would SNS do to:
| intestine
inhibit digestion/absorption
35
What would SNS do to:
| bladder
```
relax bladder
(constrict sphincter)
```
36
What would SNS do to:
| airways
alveolar dilation (allow more air to get into lungs)
37
What would PNS do to:
| heart
decrease heart rate
| decrease BP
38
What would PNS do to:
| blood vessels
blood vessels dilate
(go wherever it needs to)
-decrease BP
39
What would PNS do to:
| intestine
stimulate digestion/absorption
40
What would PNS do to:
| bladder
constrict bladder
(allow you to pee)
sphincter relaxes
41
What would PNS do to:
| airways
```
constrict airways
(save energy)
```
42
look at slide 18
ok man
43
Parasympathetic are innervated ??
cranial and sacral
44
Sympathetic are innervated ??
thoracolumbar region
45
What happens when a person loses sensory innervation of either the parasympathetic or sympathetic system?
That person now is more sensitive/responsive to any innervation or stimulation from these systems
46
understand sympathetic pathways and adrenal medulla (21 to 27)
okay man
47
sympathetic system has ???
paravertebral ganglia
48
What are paravertebral ganglia?
- located along sides of vertebrae
| - united by preganglionics into sympathetic trunk
49
preganglionic neurons of paravertebral ganglia are ______
thoracolumbar
50
postganglionic neutrons are ____
cervical to coccyx
51
In the sympathetic system there are _____ splanchnics and ______ splanchnics
cardiopulmonary
abdominopelvic
52
what are cardiopulmonary splanchnics and where do they go?
postganglionic fibers to thoracic viscera
53
what are abdominopelvic splanchnics are where do they go?
preganglionic fibres to prevertebral ganglia
postganglionic fibres to abdominopelvic viscera
54
explain the mechanism of L-tyrosine breakdown
L-tyrosine
L-DOPA
dopamine
norepinephrine
epinephrine
55
What does epinephrine activate?
sympathetic nervous system
56
List the 4 types of adrenergic receptors
alpha 1
alpha 2
beta 1
beta 2
57
What is main outcome of alpha 1 adrenergic receptor?
**activates protein kinase C
activates phospholipase C
increases Ca2+
58
What is the main outcome of alpha 2 adrenergic receptor?
**inhibits production of cAMP and therefore
-reduces cAMP-dependent protein kinase activity
also increases K hyperpolarization
59
What is the main outcome of beta adrenergic receptors?
increase cAMP and therefore
-increases cAMP-dependent protein kinase activity
60
alpha 1 adrenergic receptors have what effect ?
smooth muscle contraction
| vasoconstriction, sphincter, mydriasis
61
alpha 2 adrenergic receptors have what effect ?
inhibits NE release
inhibits insulin release
* *TRAITOR
* *inhibits sympathetic action even though it is part of the sympathetic system
62
beta adrenergic receptors have what effect ?
heart, lung, and energy regulation
-increase heart rate, contractility, bronchodilation, vasodilation, glyconeogensis, lipolysis
63
anything that increases uptake ____ activity because you are removing that drug
decreases
64
List the 5 sites to alter activity of a neurotransmitter
1) synthesis
2) storage
3) release
4) receptors
5) degradation/ termination
65
What does the SNS do to:
| eyes
pupil dilates
| contraction of iris radial muscle
66
What does the SNS do to:
| trachea and bronchioles
dilate
| allow more air to get in
67
What does the SNS do to:
| adrenal medulla
epinephrine and norepinephrine secreted
68
What does the SNS do to:
| kidney
secretion of renin
| B1 increases, A1 decreases
69
What does the SNS do to:
| ureters and bladder
relaxes bladder (detrusor)
contracts sphincter (and trigone)
70
What does the SNS do to:
| male genitalia
stimulates ejaculation
71
What does the SNS do to:
| salivary glands
slows down secretions
| makes them thicker
72
What does the SNS do to:
| heart
increased rate
| increased contractility
73
What does the SNS do to:
| GI tract
decrease in muscle motility and tone
contraction of sphincters
74
What does the SNS do to:
| female genitalia
relaxation of uterus
75
```
What does the SNS do to:
blood vessels (skeletal muscle)
```
dilate
76
```
What does the SNS do to:
blood vessels (skin, mucous membranes, splanchnic area)
```
constrict (so that more blood can go to the muscles)
77
What does the PNS do to:
| eye
contraction of iris sphincter muscle
-pupil contracts
-contraction of ciliary muscle (lens accommodates for near vision)
78
What does the PNS do to:
| trachea and bronchioles
constricts (save energy)
| increases secretions
79
What does the PNS do to:
| ureters and bladder
```
contracts bladder (detrusor)
relaxes sphincter (and trigone)
```
80
What does the PNS do to:
| male genetalia
erection
81
What does the PNS do to:
| lacrimal glands
stimulates tears
82
What does the PNS do to:
| salivary glands
stimulates copious, watery secretions
83
What does the PNS do to:
| heart
decrease rate
| decrease contractility
84
What does the PNS do to:
| GI tract
increases muscle motility and tone
85
parasympathetic pre-ganglionic neutrons are located ??
in the brain
*some exceptions
86
Parasympathetic pathways have cranial outflow in which cranial nerves?
3, 7, 9, 10
vagus nerve (10) is major preganglionic parasympathetic supply to thorax and abdomen
87
Parasympathetic pathways have sacral outflow of which sacral nerves
S2-S4
88
What are the 2 types of cholinergic receptors?
- nicotinic
| - musarinic
89
Describe nicotinic cholinergic receptors
- ligand gated ion channel
- membrane depolarization
- all preganglionic sympathetic and parasympathetic
90
muscarinic receptors (M1, M3, and M5) activate ??
- PLC (phospholipase C)
- increase Ca2+
- activate protein kinase C
* ****this is the main one
91
muscarinic receptors (M2, and M4) activate ??
- hyper polarization
- decrease cAMP
- reduces cAMP-dependent protein kinase activity
also inhibits adenylate cyclase
92
example of opposite effects at the same site
sinoatrial node
heart rate
NE (B) increases heart rate
Ach (M) decreases heart rate
93
example of opposite effects at different sites
size of pupil of the eye
NE(alpha) increases (mydriasis - dilation of pupil)
Ach (M) decreases (mitosis - constriction of pupil)
94
example of sympathetic nerves acting on parasympathetic nerve endings
NE (alpha) decreases Ach release in intestinal wall
95
example of complementary actions between SNS and PNS
male genital organ
```
PNS = erection
SNS = ejaculation
```
96
examples of organs that receive only one system
ciliary muscles of the eye- Ach
arterioles of more organs - NE
97
see slides 50 and on
ok man
