Difference between revisions of "DiffEqs"

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(Plain Bilayer Membrane)
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<math> C \frac{dV(t)}{dt} = I(t) </math>
 
<math> C \frac{dV(t)}{dt} = I(t) </math>
 +
<math> V(0) = 0 </math>
 +
 +
Here ''C'' is a constant (parameter), the ''capacitance'' of the membrane, proportional to area.
 +
 +
Next ''V(t)'' is the membrane potential.
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 +
Next ''I(t)'' is the current into the membrane, with a sign such that a positive current depolarizes the cell.  The sign conventions are TRICKY!!! I get confused all the time.
  
 
== Bilayer Membrane with Na/K Pumps ==
 
== Bilayer Membrane with Na/K Pumps ==

Revision as of 21:28, 7 February 2009

Plain Bilayer Membrane

A plain lipid bilayer is approximately an ideal capacitor. The equation for an ideal capacitor is

 C \frac{dV(t)}{dt} = I(t)  V(0) = 0

Here C is a constant (parameter), the capacitance of the membrane, proportional to area.

Next V(t) is the membrane potential.

Next I(t) is the current into the membrane, with a sign such that a positive current depolarizes the cell. The sign conventions are TRICKY!!! I get confused all the time.

Bilayer Membrane with Na/K Pumps

Bilayer Membrane with Na/K Pumps and Leak Channels

Bilayer Membrane with Na/K Pump, Leak & HH Channels