## how to plot the IV curve

The basics of how to develop, test, and use models.
xyang

### how to plot the IV curve

Thanks for the NEURON software, help a lot with my electrophysiology experiment.
I am interested in plotting the IV curve for Na current, is there a way to plot the IV curve?
Thank you very much!
Best,

Xianghong
ted
Posts: 5935
Joined: Wed May 18, 2005 4:50 pm
Location: Yale University School of Medicine
Contact:

### Re: how to plot the IV curve

The term "IV curve" is ambiguous. Sodium current is not just a function of membrane potential--it also depends on time and initial conditions. Please define what kind of IV curve you want--steady state I vs. V, instantaneous I vs. V for a particular holding potential, peak I vs. V for a series of voltage steps from a particular holding potential.
xyang

### Re: how to plot the IV curve

Hi, Ted:

We are interested in the peak I vs. V for a series of voltage steps (-60 mV to 70 mV with 10 mV steps) from a particular holding potential (-60 mV). We have a TTX sensitive transient Na current in our model.
Best,

Xianghong
ted
Posts: 5935
Joined: Wed May 18, 2005 4:50 pm
Location: Yale University School of Medicine
Contact:

### Re: how to plot the IV curve

We are interested in the peak I vs. V for a series of voltage steps (-60 mV to 70 mV with 10 mV steps) from a particular holding potential (-60 mV)
Then you need to
1. Create a single compartment model which has your voltage gated current inserted.
2. Write a program that does the following:
Runs a series of simulations in which an SEClamp applies the desired conditioning and test potentials to the model cell, while the Vector class's record method captures the time course of ina.
After each run, uses the Vector class's max or min method to detect the peak ina, and appends this to a Vector called inapeak. Also appends the test potential to another Vector called vvec.
After the very last run has been completed and analyzed, creates a Graph and uses the Vector class's plot method to plot the contents of inapeak vs. vvec (generates a plot of peak ina vs. test potential).
xyang

### Re: how to plot the IV curve

Thank you, Ted:
That helps!
Best,

Xianghong
Mao Beibei
Posts: 1
Joined: Tue Jun 01, 2021 11:20 am

### Re: how to plot the IV curve

Sorry for the sudden interruption.
I'm quite curious about the differences(both recording protocols and concrete mechanisms) between the three types of I-V curve as mentioned before and wondering what is the aim or what do we want to demonstrate when we show the specific I-V curve in the paper.
I'd appreciate it sincerely if all these questions could be solved.
ted