measured vs specific Rm
Posted: Fri Nov 01, 2013 9:28 pm
Hi all,
I would like to see how conduction velocity changes in response to changes in membrane resistance. Not just theoretically though, but using experimentally determined values. From whole-cell voltage clamp experiments I have estimates of the conduction velocity, membrane resistance and membrane capacitance, and thus tau.
Here's how I got so far:
If conduction velocity theta = 2*lambda/tau
and lambda = sqroot(Rm/Ri)
then I could determine the only missing value, the internal resistance Ri by
Ri = Rm/(theta * tau / 2)^2
My thinking was that I could then use the same equation to see what happens to the conduction velocity with different values of Rm.
However, the membrane resistance that I measured is for the whole cell, not the specific resistance per unit area. Is there some way to get around that problem? Do I really need to make some assumptions about the surface area of the cell or use one of the models from your ModelDB for what seems to be a relatively simple problem?
Any ideas or pointers in the right direction would be most appreciated.
Thanks!
I would like to see how conduction velocity changes in response to changes in membrane resistance. Not just theoretically though, but using experimentally determined values. From whole-cell voltage clamp experiments I have estimates of the conduction velocity, membrane resistance and membrane capacitance, and thus tau.
Here's how I got so far:
If conduction velocity theta = 2*lambda/tau
and lambda = sqroot(Rm/Ri)
then I could determine the only missing value, the internal resistance Ri by
Ri = Rm/(theta * tau / 2)^2
My thinking was that I could then use the same equation to see what happens to the conduction velocity with different values of Rm.
However, the membrane resistance that I measured is for the whole cell, not the specific resistance per unit area. Is there some way to get around that problem? Do I really need to make some assumptions about the surface area of the cell or use one of the models from your ModelDB for what seems to be a relatively simple problem?
Any ideas or pointers in the right direction would be most appreciated.
Thanks!