Excitability & Neuronal Activity

Question 1

Resting Membrane Potential

Answer 1

30-90 mV created mostly by Kalium channels

Question 2

Doyle et al Bacterial K+ channels

Answer 2

Streptomycine K+ channel is an integral mebrane protein with 2 transmembrane domains. Has a sequence that is homologous to all known K+ channels TVGYG

Question 3

Resting Membrane potentials

Answer 3

Verhältnis A:I, E(ion)
K+ 1:20 -80mV
Na+ 10:1 62mV
Ca2+ 10000:1 123mV
CL- 11,5:1 -65mV

Question 4

Goldmann equation

Answer 4

Vm=58 x (P[K+]out+P[Na+]out)/P[K+]in+P[Na+]in)
P = Permeability

Question 5

Molecular structure of Nav channel

Answer 5

Geschlossen bei -65mV offen bei -40mV

Question 6

Structure K+ channel?

Answer 6

4 domains with 6 subunits each.
Can be divided into inner pore, cavity and selectivity filter. Pore with amino acids that mimic hydration shell of K+ ion.