Please, can someone help me? I am trying to create a dv/dt graph after I apply the ramp protocol in the current clamp, but I am making a mistake somewhere. Can you help on how to do this graph. I created graph and ramp current recording was added. thanks a lot of.
Can you provide a bit more information about what you are trying to accomplish? What analysis software are you using? What is causing you to say it isn’t working? Is it those points in the upper right? It is unclear to me what your y-axis is meant to represent. The membrane potential at a certain time? The membrane potential at the end of the pulse? Action potential threshold?
I guess from the names of your files that you are analyzing bushy cells in the AVCN. Donata Oertel has several papers on using voltage ramps on these cells. Look at her papers for values to compare against.
Dear Caner,
Nice recordings.
The expression “dv/dt” means the instantaneous rate of voltage change over time, or the rate of change of voltage (volts per second increase or decrease) at a specific point in time.
From what I understand here you need to plot dV (maximum voltage difference in mV) in the y axis and the dT (time difference-ms) on the x axis. Larger changes in voltage (membrane potential) seems to happen within 7 ms or so, as slower (longer ramps) are not able to generate any action potential-but there smaller though significant subthreshold potential changes. For example, 1ms long ramp at 1nA current is giving you about 70 mV difference (dV = 70 mV and dT = 1ms); 2 ms long 1 nA ramp giving you 65 mV (dV =65 and dT =2 ms); say 8 ms long ramp is giving you dV of around 30 mV. You will need to measure those precisely with your cursor. So if you plot them that way it should give you an exponential decline. If you like you can fit those with an exponential(s) and find out the time constant (s). These values you may compare among individual cells or groups of cells depending on what you are aiming at. For example some people use it/these values for comparing excitability and capacitance.
Best wishes,
Refik
- Badges
- Science topic
- Similar topics
- Mathematical Sciences
- Graphs