I-V relationship in CA1 cell

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Daniel morgan
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I-V relationship in CA1 cell

I am currently measuring I-V relationship in CA1 cell. I applied a voltage step from -70 to +40. However, the I-V curve dose not pass through zero. Does it mean that I had a bad clamp ( I am stimulating the schaffer collateral) ? What can be other possibilities ?

The FFM
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any chance you can attach a

any chance you can attach a .jpg of the IV curve for that cell please?

Daniel morgan
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Actually, what I mean is the

Actually, what I mean is the I-V reverse at +20mV instead of 0mV. Any idea ?

patchclamper
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Have you corrected the

Have you corrected the juction potential? It's possible that the junction potential between your intracellular and ACSF is around 20mv so when you clamp at 20mv your are actually clamp at 0 mV.

Also, do you have GABA receptor blocker (eg. picrotoxin) in your ACSF? It is also possible that when you stimulate schaffer collateral, you are getting some GABA mediated IPSCs which will also change the reverse potential depent on the Cl- reversal potential of your system.

Daniel morgan
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Yes, seriously thinking about

Yes, seriously thinking about the problem with junction potential now. Calculate it and it is about 12 mV. I have GABA blocker in my ACSF. Another problem now is to minus the LJP from my original I-V. Just don't like that. Thinking about changing my intra-solution. That may be easier for future exp.