action potential and myelin

Question 1

What does furosemide act on? where?

Answer 1

Na-K-Cl symporter in TAL of LOH

Question 2

what is regulated by the potential in voltage gated channels

Answer 2

the probability of a channel being open

Question 3

what do you call it when a channel closes in the presence of a stimulus

Answer 3

inactivation (voltage) or desensitization (ligand)

Question 4

inactivation process

Answer 4

closed channel=neg charges in channel screened. Open channel=neg charges exposed to + charges on “ball” and attraction and steric blocking occurs

Question 5

H and H model of ion channel gating

Answer 5

HMMM particles. Movement of 3 Ms required to open followed by movement of H to inactivate

Question 6

refractory period is due to

Answer 6

sodium channel inactivation and repriming

Question 7

V=

Answer 7

IR

Question 8

effects of myelin

Answer 8

increased membrane resistance (increased length constant), decreased membrane capacitance (faster membrane chargin), Decreased metabolic requirements

Question 9

mutation in benign familial neonatal seizures

Answer 9

mutations in K channel

Question 10

temperature dependent depolarization and therefore febrile seizures are dependent on___

Answer 10

L type Ca channels