cation anion

+_

OUTSIDE OF CELL

INSIDE OF CELL

K+

Cl-Na+

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

K+ A-

Na+ Cl-

18

Na-K Pump Animationhttp://highered.mcgraw-hill.com/olc/dl/120068/bio03.swf

19

Na+ Opens

K+ Opens

Na+ becomes Refractory

K+ continuesto leave cell.Causing themembranepotentialto return tothe restingpotential.

K+ channelsclose.

Na+ channelsreset, readyfor action again!Extra K+ outside

diffuses away.

31

32

33

34

Lai et al. Nature Reviews Neuroscience 7, 548–562 (July 2006) | doi:10.1038/nrn1938

37

Synaptic Transmission