Intro to autonomic nervous sys (respi)

Question 1

What does grey matter comprise of?

Answer 1

Dorsal and ventral horn

Question 2

What is CNS and what does it consist?

Answer 2

Central nervous sys

Brain and spinal cord

Question 3

What is PNS and what does it consist?

Answer 3

Peripheral nervous sys

Structures that exit/enter into brain (cranial/spinal nerve)

Question 4

Somatic vs visceral nervous sys

Answer 4

Somatic
- conscious -> sensory from skin and joints
- voluntary motor -> skeletal muscle

Visceral
- subconscious -> sensory from organs (except visceral pain)
- involuntary motor -> smooth/cardiac muscles and glands

Similarities
- both need stimulus, receptors, afferent (sensory) nerve carrying info to CNS, efferent (motor) nerve to bring back info from CNS to effectors

Question 5

How do visceral reflex afferent nerve fibres travel?

Answer 5

Travel tgt w/ parasympathetic fibres

Question 6

What is visceral pain?

Answer 6

Pain from internal environment

Question 7

Characteristics of visceral pain?

Answer 7

Not well localised

Referred

Question 8

Causes of acute visceral pain

Answer 8

Obstruction

Inflammation

Ischemic

Question 9

Characteristics of visceral pain

Answer 9

Reach consciousness

Question 10

How do visceral pain afferent nerve fibres travel?

Answer 10

Together w/ sympathetic fibres

Question 11

What is spinothalamic pathway?

Answer 11

Carry pain info to brain for interpretation
- can’t differentiate origin of pain

Question 12

Mechanism of referred pain

Answer 12

Convergence theory
- sensory nerve converge onto second-order neurons at same segment -> pain from internal organ referred elsewhere (at area whr organ is NOT located at)

Question 13

How many neurons does viscero-motor/autonomic NS use to go from spinal cord to target tissue?

Answer 13

2
- pre-ganglionic neuron
- post-ganglionic neuron

Question 14

Where do autonomic neurons arise from?

Answer 14

Lateral horn

Question 15

What does ANS supply?

Answer 15

Smooth muscles

Cardiac muscles

Glands

Question 16

Characteristics of cell bodies of pre- and post-ganglionic neuron

Answer 16

Pre -> cell bodies always within CNS

Post -> cell bodies always within PNS

Question 17

Features of pre-ganglionic nerve fibers

Answer 17

Myelinated -> whiter
- transmission of info is much faster

Short

Question 18

Features of post-ganglionic nerve fibres

Answer 18

Unmyelinated -> grey

Long

Question 19

Neurotransmitters of the ANS (preganglionic synapse)

Answer 19

Sympathetic - ACh
Parasympathetic - ACh

Question 20

Neurotransmitters of the ANS (postganglionic synpase)

Answer 20

Sympathetic - noradrenaline (adrenergic/sympathetic nerves)

Parasympathetic - ACh (cholinergic/parasympathetic nerves)

Question 21

Features of pre-ganglionic neurons

Answer 21

CNS

Intermedio-lateral nucleus (ILN) -> aggregation of cell bodies
- located in lateral horn of spinal cord (T1-L2) segments

Question 22

Features of post-ganglionic neurons

Answer 22

PNS

Mainly in sympathetic chain/trunk ganglia
- found in neck all the way to pelvic cavity
- aka para-vertebral ganglia -> parallel to vertebral column

Some in pre-vertebral ganglia
- in front of abdominal aorta and vertebral column

Some in adrenal medulla

Question 23

Where can pre-ganglionic neurons be found?

Answer 23

Brainstem nuclei
- related to CN 3, 7, 9 and 10 -> near organs that they supply

Sacral parasympathetic nucleus
- lateral horn of spinal cord (S2-S4)
- cranio-sacral outflow

Question 24

Where can post-ganglionic neurons be found?

Answer 24

Located in organ/near organ that the parasympathetic nervous sys supply

Question 25

Special feature of splanchnic nerve

Answer 25

Pass through w/o synapse at sympathetic trunk ganglia

Synapse at pre-vertebral ganglia/adrenal gland

Question 26

Name of flow for sympathetic nerves

Answer 26

Thoraco-lumbar outflow