Unit 5 Lecture 40 Flashcards
Name the major classes of neuromuscular disease
- Motor neuron degeneration
- Neuromuscular transmission failure
- Dystrophic myopathies
- Metabolic myopathies
What is motor neuron degeneration?
Efferent AP fail to reach effector, due to motor neuron degeneration or loss of myelin on axons
What are two cases of motor neuron degeneration?
- Amyotropic lateral sclerosis (ALS)
- Multiple sclerosis (conduction failure)
What is neuromuscular transmission failure?
Motor neuron action potential arrives at neuromuscular junction but fails to cause sufficient muscle excitation
What are two cases of neuromuscular transmission failure?
Myasthenia Gravis or lambert eaton syndrome
What is the difference between Myasthenia gravis and lambert eaton syndrome?
MG = body makes antibodies against Ach receptors -> Ach can’t open ligand-gated channels -> no muscle AP
LES = body produces antibodies against voltage-gated Ca+ channels -> can’t produce Ach -> no AP
What is dystrophic myopathies?
Weakness and loss of muscle fibers
What is an example of dystrophic myopathies?
Muscular dystrophy
What is metabolic myopathies?
Metabolic disorders where coding genes that help w ATP are mutated
What is an example of metabolic myopathies?
McArdle’s Myopathy
What was Lou Gehrig’s life span?
June 19, 1903 - June 2, 1941
What is the toxin found in Funnel web spiders called?
Atracotoxin “ACTX”
What does ACTX attack?
blocks the closing of the inactivation gate of the voltage gated sodium channels
What 2 things does ACTX do?
- lengthens AP -> long plateau of depolarization
2. Causes spontaneous repetitive firing of AP w/ increasing frequency
What saved Gordon Wheatley’s life?
Antivenom
