I've recorded Na+ currents from neurons and I'm trying to fit activation and steady-state deactivation curve.
External sodium conc. was 127mM and internal was 8.6 mM.
ENa is 67.8 mV predicted by the Nernst equation
but actual extrapolated reversal potential was near +42 mV
This deviation possibly arose from contamination outward currents or non-linearity arising form Goldman-type rectification.
Here is my question.
When I fit the activation curve, which value should I use for VNa in cord conductance equation
( GNa = INa(Vm-VNa) ? ....42 mV (actual reversal potential) or 67.8 mV(preducted ENa)
Thanks in advance.