Neuro physiology

Question 1

pseudo unipolar neurone - how many neurites?

Answer 1

one neurite that bifurcates

Question 2

most excitable part of neurone

Answer 2

axon hillock and initial segment

Question 3

Axon with a large/small? diameter can conduct an AP at greater velocity

Answer 3

Large diameter

lower resistance

Question 4

Microglia: oligodendrocytes/schwann cells -which ones are found in the CNS?

Answer 4

CNS: oligodendrocytes

Question 5

most excitable parts along an axon

Answer 5

nodes of ranvier (myelin sheath gaps)

Question 6

name of nerve conduction in myelinated axons

Answer 6

saltatory conduction

Question 7

most common excitatory and inhibitory transmitters in the CNS

Answer 7

excitatory: glutamate
inhibitory: GABA or glycine

Question 8

inhibitory neurotransmission involves efflux of ?

Answer 8

K+

Question 9

excitatory NTM involves influx of ?

Answer 9

Na+

Question 10

LMN’s

alpha innervate ?-fusal fibres and gamma innervate ?-fusal fibres

Answer 10

alpha LMN’s innervate extra-fusal fibres

gamma LMN’s innervate intra-fusal fibres

Question 11

where are golgi tendon organs located

Answer 11

at the junction of the muscle and tendon

Question 12

what do golgi tendon organs monitor

Answer 12

changes in muscle tension

|&raquo_space; protect muscle from overload

Question 13

what type of sensory afferents innervate golgi tendon organs

Answer 13

1b

Question 14

When 1b afferent is excited, is alpha-MN inhibited or excited?

Answer 14

alpha-MN INHIBITED by excitation of 1b afferent

Question 15

what is the crossed extensor reflex

Answer 15

opposite leg extends to stop you falling over when the other leg flexes in response to noxious stimulus

Question 16

Rubrospinal tract is responsible for limb ..?

Answer 16

flexors

Question 17

Vestibulospinal tract is responsible for limb ..?

Answer 17

extensors

Question 18

reticulospinal tract
which is medial - pontine or medullary?
which enhances antigravity reflexes?

Answer 18

pontine is medial, medullary is lateral
pontine enhances antigravity muscles&raquo_space; contraction of lower limb
medullary opposes this&raquo_space; relaxes antigravity muscles

Question 19

State functions of each fibre type:
A-alpha
A-beta
A-delta
C

Answer 19

A-alpha: proprioceptors of skeletal muscle
A-beta: mechanoreceptors of skin
A-delta: pain and temperature
C: temperature, pain, itch

Question 20

In what laminae do nociceptive A-delta and C fibres terminate

Answer 20

I and II (and also V for A-delta)

Question 21

Nociceptive pathway:
which causes primary and which causes secondary hyperalgesia
a) Peripheral sensitisation 
b) central sensitisation 
which one plays a major role in heat?

Answer 21

Peripheral sensitisation > Primary hyperalgesia
- plays a major role in heat

Central sensitisation > secondary hyperalgesia
(underlies pain that persists after tissue healing)

Question 22

what is viscerosomatic pain like?

Answer 22

sharp and well localised

Question 23

what contains axons of the nerve cells - white matter or grey matter?

Answer 23

White matter contains axons

Grey matter contains cell bodies of the nerve cells

Question 24

what does the central canal contain

Answer 24

CSF

Question 25

Pain evoked by nociceptors can be simultaneously reduced by activity in ?

Answer 25

A-beta fibres

Question 26

When should tramadol be avoided?

Answer 26

epilepsy

Question 27

Pethidine should NOT be used in combo with ?

Answer 27

MAOI

Question 28

example of weak opiod

Answer 28

codeine, dihydrocodeine

Question 29

NSAIDs inhibit the accumulation of ? by inhibiting the enzymes ?

Answer 29

prostaglandins

COX 1 and 2

Question 30

COX2 selective inhibitors are not really used due to being ?

Answer 30

prothrombotic

Question 31

PGE2 produced by COX-1 protects against ?

Answer 31

GI damage from acidic environment

Question 32

Long term NSAIDs can cause ?toxicity

Answer 32

nephrotoxicity

Question 33

Does neuropathic pain respond to NSAIDs?

Answer 33

no

Question 34

2 drug classes used for neuropathic pain + examples

Answer 34

Anti-epileptics

• Gabapentin
• pregabalin

Tricyclic antidepressants

• amitriptyline
• nortryptiline

Question 35

a) painful diabetic nephropathy

b) migrane prophylaxis gabapentin or pregabalin?

Answer 35

a) pregabalin

b) gabapentin

Question 36

first line tx to control pain and intensity of attacks in trigeminal neuralgia

Answer 36

carbamazepine