Ch 14: Autonomic NS Flashcards
(89 cards)
1
Q
What does the ANS motor neuron do?
A
Innervate smooth and cardiac muscle, and glands.
Make adjustments to ensure optimal support for body activities.
Operate via subconscious control.
2
Q
What are the differences between somatic and autonomic NS?
A
- Effectors.
- Efferent pathways and ganglia.
- Target organ responses to neurotransmitters.
3
Q
What is the effector for Somatic NS?
A
Skeletal muscles
4
Q
What are the effectors of the ANS?
A
- Cardiac Muscle
- Smooth Muscle
- Glands
5
Q
What is the efferent pathways and ganglia of the Somatic NS?
A
- Cell body in CNS
2. Thick, myelinated, group A fiber extends in spinal or cranial nerve to skeletal muscle
6
Q
What are the 2-neuron chains of the ANS?
A
- Preganglionic neuron (in CNS)
2. Postganglionic (ganglionic) neuron in autonomic ganglion
7
Q
What are Postganglionic (ganglionic) neurons?
A
Outside CNS has nonmyelinated postganglionic axon that extends to effector organ
8
Q
What are preganglionic (ganglionic) neurons?
A
thin, lightly myelinated preganglionic axon
9
Q
What are the neurotransmitter effects of the somatic NS?
A
- Releases ACh
2. Always stimulatory
10
Q
What are the neurotransmitter effects of the ANS?
A
- Preganglionic fibers release ACh.
- Postganglionic fibers release norepinephrine or ACh at effectors.
- Effect is either stimulatory or inhibitory, depending on type of receptors.
11
Q
What are some of the overlaps of the somatic and autonomic functions?
A
- Most spinal and cranial nerves contain both
2. Adaptions involve skeletal muscles and visceral organs
12
Q
What are the divisions of the ANS?
A
Sympathetic division
Parasympathetic division
13
Q
What is dual innervation?
A
All visceral organs served by both divisions, but cause opposite effects.
14
Q
What is Dynamic antagonism?
A
Two divisions that maintain homeostasis
15
Q
What is the role of the parasympathetic division?
A
Promotes maintenance activities and conserves body energy.
16
Q
What would occur when the Parasympathetic is activated?
A
- Blood pressure, heart rate, and respiratory rates are low
- Gastrointestinal tract activity high.
- Pupils constricted; lenses accommodated for close vision
17
Q
What is the role of the sympathetic division?
A
Mobilizes body during activity; “fight-or-flight” system
18
Q
When would Sympathetic activated?
A
vigorous physical activity
19
Q
What would occur when the Sympathetic is activated?
A
- Shunts blood to skeletal muscles and heart.
- Dilates bronchioles.
- Causes liver to release glucose
20
Q
What is SLUDD?
A
Occurs during the activation of Parasympathetic
Salivation, Lacrimation, Urination, Digestion and Defecation
21
Q
What are the characteristics of long preganglionic fibers?
A
- Extend from CNS almost to target organs.
- Synapse with postganglionic neurons in terminal ganglia close to/within target organs.
- Short postganglionic fibers synapse with effectors
22
Q
Where are cell bodies located?
A
Brain stem
23
Q
What nerves targets smooth muscle of eye?
A
Oculomotor nerves (III)
24
Q
What nerves stimulate large glands in head?
A
Facial nerves (VII)
25
What are the ganglia involved with Oculomotor nerves (III)?
Ciliary ganglia
26
What are the ganglia involved with Facial nerves (VII)?
pterygopalatine ganglia and submandibular ganglia
27
What nerves stimulate the parotid salivary glands?
Glossopharyngeal nerves (IX)
28
What ganglia is involved with Glossopharyngeal nerves (IX)?
Otic ganglia
29
What nerves stimulate the neck and nerve plexuses for ~ all thoracic and abdominal viscera?
Vagus nerves (X)
30
What are the ganglia involved with Vagus nerves (X)?
Cardiac, pulmonary and esophageal plexuses
31
What does the sacral part of the parasympathetic division stimulate?
Serves pelvic organs and distal half of large intestine (urinary bladder, ureters, reproductive organs)
32
Where are the Preganglionic neurons of the sympathetic located?
T1-L2
33
Where would Preganglionic fibers of the sympathetic division enter?
Sympathetic trunk (chain or paravertebral) ganglia
34
How many paravertebral ganglia are in the sympathetic trunk? Where are they located?
```
23
Cervical: 3
Thoracic: 11
Lumbar: 4
Sacral: 4
Coccygeal: 1
```
35
What does the ganglion short preganglionic fiber does when entering sympathetic trunk?
1. Synapse with ganglionic neuron in same trunk ganglion.
2. Ascend or descend sympathetic trunk to synapse in another trunk ganglion.
3. Pass through trunk ganglion and emerge without synapsing (only in abdomen and pelvis).
36
Where is the location when preganglionic fibers pass without synapsing?
Adrenal medulla
37
What do medullary cells secrete in the blood?
Norepinephrine and epinephrine
38
What gland is "misplaced" sympathetic ganglion?
Adrenal medulla
39
What does visceral pain contribute to?
Referred pain
40
What is the process of the visceral reflex arcs?
1. Stimulus
2. Receptor in viscera
3. Visceral sensory neuron
4. Integration center
5. Motor neuron
6. Visceral effector
7. Response
41
What fibers release ACh?
Cholinergic fibers
42
What are considered cholinergic fibers?
1. All ANS pregonglionic axons
| 2. All parasympathetic postganglionic axons at effector synapse
43
What fibers release Norepinephrine?
Adrenergic
44
What are considered adrenergic fibers?
1. Most sympathetic postganglionic axons
| 2. Exception: sympathetic postganglionic fibers secrete ACh at sweat glands
45
What are the receptors that bind to Ach?
1. Nicotinic
| 2. Muscarinic
46
What are the classes of adrenergic receptors?
Alpha (a1-2)
| Beta (B1-3)
47
Where are nicotinic receptors found?
1. Sarcolemma of skeletal muscle cells at NMJ.
2. All postganglionic neurons (sympathetic and parasympathetic).
3. Hormone-producing cells of adrenal medulla.
48
What is the effect of ACh binding to nicotinic receptors?
Stimulatory
Opening ion channels
Depolarizing postsynaptic cell
49
Where are muscarinic receptors found?
All effector cells stimulated by postganglionic cholinergic fibers
50
What is the effect of ACh binding to muscarinic receptors?
Inhibitory or excitatory depending on target organ
51
What is the effect of atropine?
Anticholinergic; blocks muscarinic ACh receptors
52
What is the purpose for atropine?
Used to prevent salivation during surgery, and to dilate pupils for examination
53
What is the effect of neostigmine?
Inhibits acetylcholinesterase that breaks down Ach
54
What is the purpose of neostigmine?
Used to treat myasthenia gravis
55
What is the effect of Over-the-counter drugs for colds, allergies, and nasal congestion?
Stimulate a-adrenergic receptors
56
What is the effect of Beta-blockers?
Drugs that attach to B2 receptors to dilate lung bronchioles in asthmatics; other uses
57
Are most visceral organs dual innervated?
Yes
58
What is the purpose of sympathetic tone?
Keeps blood vessels in continual state of partial constriction
59
What division controls BP at rest?
Sympathetic
60
Why do sympathetic fibers fire more rapidly?
Constrict blood vessels and cause blood pressure to rise
61
Why do sympathetic fibers fire less rapidly?
To prompt vessels to dilate to decrease blood pressure
62
What does alpha-blocker drugs do?
Interfere with vasomotor fibers and used to treat hypertension
63
What does the parasympathetic division dominate?
1. Heart
2. Smooth muscle of digestive
3. Urinary tract organs
4. Most glands except for adrenal and sweat glands
64
What happens to the parasympathetic in times of stress?
Sympathetic division can override effects
65
What do the drugs that block parasympathetic responses do?
Increase heart rate and cause fecal and urinary retention
66
In regards to cooperative effects what do parasympathetic fibers do?
Vasodilation
| Responsible for erection of penis or clitoris
67
In regards to cooperative effects what do sympathetic fibers do?
Ejaculation of semen in males
| Reflex contraction of a female's vagina
68
What parts of the body only receive sympathetic fibers?
1. Adrenal medulla
2. Sweat glands
3. Arrector pili
4. Muscles
5. Kidneys
6. Most blood vessels
69
What does the sympathetic division control?
1. Thermoregulatory responses to heat.
| 2. Release of renin from kidneys.
70
What are the metabolic effects of the sympathetic?
1. Increases metabolic rates of cells.
2. Raises blood glucose levels.
3. Mobilizes fats for use as fuels
71
What is the difference between parasympathetic and sympathetic in localization?
Para: short-lived, highly localized control over effectors
Sym: longer-lasting, bodywide effects
72
What destroys ACh?
Acetylcholinesterase
73
What is the hypothalamus?
Main integrative center of ANS activity
74
What is the subconscious cerebral?
Input via limbic system structures on hypothalamic centers
75
What aspects of the body does the hypothalamus control?
1. Heart activity and blood pressure.
2. Body temperature, water balance, and endocrine activity.
3. Emotional stages (rage, pleasure) and biological drives (hunger, thirst, sex).
4. Reactions to fear and "fight-or-flight" system
76
What does connections of the hypothalamus to limbic allow?
Cortical influence on ANS
77
What is biofeedback?
1. Awareness of physiological conditions with goal of consciously influencing them.
2. Biofeedback training allows some to control migraines and manage stress.
78
Can the cortical control be voluntary?
Yes
79
What is hypertension?
Overactive sympathetic vasoconstrictor response to stress
80
What treats hypertension?
adrenergic receptor - blocking drugs
81
What is Raynaud's disease?
Exaggerated vasoconstriction in fingers and toes causing cyanotic and pain
82
How is Raynaud's treated?
Vasodilators
83
What is autonomic dysreflexia?
Uncontrolled activation of autonomic neurons in quadriplegics and those with spinal cord injuries above T6 and blood pressure skyrockets, life threatening
84
What are the effects of age on ANS?
Constipation
Dry eyes
Frequent eye infections
Orthostatic hypotension
85
What a B1 receptors?
Increase heart rate and force contraction stimulating kidneys to release renin
86
What are B2 receptors?
Inhibitory: dilates blood vessels and bronchioles, relaxes the smooth muscle walls of digestive urinary and uterus
87
What are B3 receptors?
Stimulate lipolysis by fat cells
88
What are a1 receptors?
Constrict blood vessels and visceral organs, dilates pupils
89
What are a2 receptors?
Inhibit NE release from adrenergic terminals, inhibits insulin secretion, promotes blood clotting
