Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOL21332 - Motor Systems > Lecture 8 - Diseases of the motor unit > Flashcards

Lecture 8 - Diseases of the motor unit Flashcards

1
Q

What are diseases within the skeletal muscle fibres called?

A

Myogenic diseases/Myopathies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are diseases within the neuromusclular junction/synapse called?

A

Neuromusclular transmission diseases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are diseases within the Motorneurons called?

A

Neurogenic diseases/Neuropathies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two types of neuropathy? [2]

A
  • Motor neuron diseases (cell body)

- Peripheral neuropathies (axon & myelin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the functional units of a Motor unit?

A
  • Cell body of motor neuron
  • Axon of motor neuron
  • Neuromuscular junction (synapse)
  • Muscle fibres
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name a neuromuscular disease.

A

Myasthenia gravis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the symptoms of Myasthenia gravis?

A

Reduced number of nicotinic ACh receptors or reduced interaction of ACh with receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Guillain-Barré Syndrome?

A

Rapid onset muscle weakness caused by autoimmune damage to the peripheral nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a common feature Neuropathies and Myopathies?

A

Muscle weakness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the three types of muscle wasting? [3]

A
  • General wasting
  • Distal wasting
  • Proximal wasting
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What type of muscle wasting is linked to Neurogenic diseases?

A

Distal limb weakness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What type of muscle wasting is linked to Myopathic diseases?

A

Proximal limb weakness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are fibrillations?

A
  • Small spontaneous twitches of single muscle fibres

- Not visible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are Fasciculations?

A
  • Small visible muscles twitches

- Single motor units firing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are features of lower motor neuron lesions?

A
  • Primary MNs, innervate skeletal muscle directly

- Weakness, atrophy, decreased tendon relfexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are features of upper motor neuron lesions?

A
  • Originate from higher motor centre, synapse with LMNs

- Weakness, increased tendon relfexes

17
Q

What are tests that can be performed to distinguish Neurogenic and Myogenic disease? [5]

A
  • Measure muscle enzymes in serum
  • Electromyography
  • Nerve conduction studies
  • Muscle biopsy
  • DNA analysis
18
Q

What enzymes are likely to be found in the serum of damaged muscle?

A
  • Creatinine kinase

- Lactate dehydrogenase

19
Q

How much serum enzyme is expected in Myopathic diseases?

A

Large increases

20
Q

How much serum enzyme is expected in Neuropathic diseases?

A

Small increases

21
Q

How does electromyography work?

A
  • Intramusclular electrodes

- Records APs of single motor units and groups of motor units

22
Q

What are the four main measurements taken during Electromyographies?

A
  • Spontaneous activity at rest
  • Number of MUs under voluntary control
  • Duration and amplitude of MU APs
  • Changes over time/stimulations
23
Q

What is the EMG like in normal muscle?

A
  • No spontaneous activity at rest
  • Weak contractions allow for single motor units to be measured
  • Maximal` contractions causes interference
24
Q

What is the EMG like in neurogenic disease?

A
  • Fasciculations/ fibrillations occur at rest
  • Reduced interference patterns (some MNs lost)
  • Remaining MNs contact more muscle fibres than normal
25
Q

What is the EMG like in myogenic disease?

A
  • Loss of muscle fibres
  • No activity at rest
  • Each MU has fewer surviving muscle fibres
26
Q

What is a nerve conduction study?

A
  • Record surface EMG
  • Stimulate motor nerve at 2 sites
  • Measure latencies
  • Measure distance
27
Q

What does a Nerve conduction study provide information on?

A
  • Conduction velocities

- Amplitude of muscle APs

28
Q

What can a muscle biopsy show?

A
  • Atropies
  • Hypertropies
  • Muscle necrosis
29
Q

What can genetic testing show?

A
  • Genes associated with suspected disease
30
Q

What are the limited to genetic testing?

A

Numerous genes are often involved with NM diseases

BIOL21332 - Motor Systems (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions