CNS channelopathies

Question 1

What is episodic ataxia, and what are its general symptoms

Answer 1

Episodic ataxia= irregular, uncontrolled muscle contraction. 2 main types
General symptoms:
ataxia, trunk instability, vomiting, dizziness, nausea, headache

Question 2

Summary of genetic cause and treatment for episodic ataxia type 1

Answer 2

Loss of function mutation in Kv channel
in cerebellum
increased excitability due to slow/delayed repol
Treatment= phenytoin and carbamazpine (Na+ channel blockers)

Question 3

Summary of genetic cause and treatment for episodic ataxia type 2

Answer 3

Loss of function mutation in Cav
cells (purkinje and granule) stuggle to release neurotransmitter
problems with control of skeletal muscle
3 allelic disorders associated with CACNA1A
Treatment= acetazolamide) carbonic anhydrase inhibitor

Question 4

What are the different ion channel mutations in inhibitory and excitatory neurons associated with epilepsy

Answer 4

Nav1.1- loss
GABAaR- loss
AchR- gain
Nav1.2- gain
HCN- loss
Kv7.2- loss

Question 5

What 2 factors determines what type of epilepsy a patient has

Answer 5

The type and position of the mutation they possess (NAv1.1- miss-sense and truncation mutations associated with epilepsy)