Neuromuscular Disease Flashcards
How does curare affect cholinergic transmission and muscle contraction?
Competes for and blocks ACh receptor so no muscle stimulation occurs
Curare is only toxic when administered how?
Intravenous
Intramuscular
How does Botox affect cholinergic transmission and muscle contraction?
Cleaves proteins involved in ACh vesicle formation and blocks vesicle docking to prevent exocytosis
What happens molecularly in Lambert Eaton myasthenic syndrome?
Antibodies attack presynaptic Ca channels resulting in less NT release
Which cancer is associated with Lambert Eaton syndrome?
Small cell carcinoma
Which disease is the most common neuromuscular junction disorder?
Myasthenia gravis
Autoantibodies attack what in myasthenia gravis?
ACh receptors
When do symptoms start in myasthenia gravis?
When ACh receptors reduced to 30% of normal
A patient must have Autoantibodies to suggest myasthenia gravis. True/False?
False
Patient with fatigue without antibodies may still have it
Which organ must be screened/assessed in people with myasthenia gravis?
Thymus (arrange CT chest to check for thymoma)
Females are more affected than males by myasthenia gravis. True/False?
True
List clinical features of myasthenia gravis
Fluctuating weakness
Tiredness at end of the day
Ocular signs (ptosis)
What is the treatment for myasthenia gravis?
Acetylcholinesterase inhibitor (pyridosigmine) Thymectomy
What are muscle fasciculations?
Visible fine fast spontaneous twitches that occur in denervated muscle that become excited
What is myotonia?
Failure of muscle relaxation after use
