autonomic nervous system

Question 1

central autonomic nervous system

Answer 1

subconscious but conscious override

Question 2

peripheral autonomic nervous system

Answer 2

sympathetic and parasympathetic

Question 3

what is SNS’s job?

Answer 3

fight or flight

Question 4

SNS origins

Answer 4

thoracolumbar (T1-L2/3) (except the cervical ganglia which supplies the head)

Question 5

SNS ganglia location

Answer 5

next to the spinal chord

Question 6

SNS NTs

Answer 6

preganglionic synapse - ACH
postganglionic synapse - noradrenaline (except sweat glands and deep blood vessels - ACH)

Question 7

SNS response

Answer 7

dilated pupils
dry mouth
uncongested nose
adrenaline release
chronotropy inotropy (heart)
vasodilation
smooth muscle in bronchi relax
constipation -> reduce GI blood supply
urinary retention/ fluid retention
renal (vasoconstriction -> increase renin -> further vasoconstriction)
reduce excessive heat

Question 8

SNS receptors

Answer 8

Alpha 1 + 2
- 1 = arteriole constriction
- 2 = venous constriction (and coronary artery)
Beta 1 + 2
- 1 = heart (increase heart, increase contractility)
- 2 = lungs, uterus, skeletal blood vessels, bladder, eye, gut ,smooth muscle relaxation
agonist and antagonist of each

Question 9

SNS receptor-targeted drugs

Answer 9

alpha 2 agonist - yohimbine
- medicine in vet practice
Beta 2 agonist - salbutamol
- asthma inhaler
- also used in premature labour (stop uterine stimulation)
Beta 1 agonist - atenolol
- lowers blood pressure
- taccharrthymia
- secondary MI prevention

Question 10

what is the role of the parasympathetic nervous system?

Answer 10

rest and digest

Question 11

PNS origins

Answer 11

craniosacral outflow
- cranial - 3 (oculomotor), 7 (facial/ otic ganglia), 9 (glossopharyngeal), 10 (vagus) nerves
- sacral - S2,3,4

Question 12

PNS ganglia

Answer 12

near site of action
- cervical -> cervical area
- thoracic -> heart and lungs
- coeliac -> gut and genitourinary

Question 13

PNS NTs

Answer 13

ACH in pre and post ganglionic synapse

Question 14

PNS response

Answer 14

• pupillary constriction - improves near vision
• nasal engorgement
• excess salivation
• increased gastric secretions and blood flow
• slow heart rate
• broncho constriction
• micturition/ defecation/ ejaculation
• lacrimation

Question 15

PNS receptors

Answer 15

muscarinic receptor (muscular)
- most in CNS (M2/M3)
- M2 = heart
- M3 = salivary glands, gut, bladder, blood vessels, eye
nicotinic receptor
- NMJ
- N2 - mainly in autonomic ganglia; some in brain

Question 16

PNS receptor-targeted drugs

Answer 16

muscarinic receptor antagonist (M2)
- atropine
- reduces effect of ACH on the heart
- increases heart rate
M1 agonist - Xanomeline
- potential treatment of Alzheimer’s and Sz
N1 antagonist - succinylcholine
- stimulation, depolarised, muscle spent ad then paralysed
N2 antagonist - vecuronium bromide
- non-depolarising muscle blocker

Question 17

autonomic dysfunction - CVS

Answer 17

Brady tachycardia; hypotension

Question 18

autonomic dysfunction - GI

Answer 18

GI disturbance, excess salivation

Question 19

autonomic dysfunction - vascular

Answer 19

flushing, excess sweating

Question 20

autonomic dysfunction - eyes

Answer 20

visual disturbances

Question 20

autonomic dysfunction - GU

Answer 20

urgency, incontinence

Question 21

autonomic dysfunction - adrenal

Answer 21

feeling of dread/ panic

Question 21

autonomic dysfunction - respiratory

Answer 21

wheeze

Question 22

autonomic dysfunction - sexual

Answer 22

erectile dysfunction

Question 23

functions of the brain stem

Answer 23

cranial nerve function conduit function integrative functions

Question 24

brain stem death

Answer 24

paralysis and unconsciousness apnoea loss of cranial nerve function - coning

Question 25

enteric nervous system

Answer 25

manages how the body digests food

Question 26

testing for brain stem death

Answer 26

two people must be present - one does the procedure and the other watches; few hours later they swap roles - thin plastic tube placed down throat to see if they gag - disconnected from ventilator for a short period of time to see if they attempt to breathe on their own - eye is stroked with paper or cotton to provoke a response - pressure on the forehead