Neuroscience Test 1 - Small Group 3
Terms
undefined, object
copy deck
- Which nerve rootlets are invaded by a Pancoast tumor?
-
Cervical - VIII
Thoracic - I - What is the resulting syndrome of the interruption of sympathetic nerve fibers from the superior cervical ganglion
- Horner's Syndrome
- Why is there weakness associated with this disease?
- There is an autoimmune response that attacks the P/Q Ca channels in the synapse. This does not allow Ach to be efficiently released.
- Why does excercise reduce the weakness?
- With prior activity (exercise), Ca2+ builds up in the pre-synaptic neuron and permits greater ACh release, somewhat rescuing the muscle activity.
- How long to SCLC patients live if untreated?
- 6-17 weeks
- What drug is the main drug used to help the muscle weakness?
- Neostigmine
- What three things does LES present with?
-
1. Proximal muscle weakness
2. Lack of tendon reflexes
3. Dysfunction of autonomics - How does LES affect the compound AP produced after continuous contraction?
- Reduced compound muscle action potential that shows potentiation following contraction.
- In LES are the minature endplates normal? How about the AchRs?
- Miniature EPPs (single quanta) are normal-- as are muscle ACh receptors
- How do the antibodies against the Ca channels affect the channels?
- Reduced Ca2+ influx is not due to blockade of channel directly-- hypothesis is that the autoantibody cross-links to the channel antigen and increases its rate of channel internalization.
- What type of tissue do SCLC develop from?
- SCLCs develop from neuroectoderm -- will be related to neural tissue.
- What happens to the normal quantal release in a LES patient?
- It is reduced due to the reduction of Ca influx. This means less vesicles fuse to release Ach.