Hey Viola,
To compute the APD90 (Action Potential Duration at 90% repolarization), you need the time series data representing the voltage during an action potential. Here's a general approach to calculate APD90:
- Obtain the voltage values during the action potential at regular intervals (e.g., in milliseconds). You should have a series of voltage values that represent the entire duration of the action potential.
- Identify the peak of the action potential. This is typically the highest voltage value reached during the depolarization phase.
- Measure the voltage value at 90% repolarization. Repolarization is the phase when the voltage returns to its resting state or near-resting state. Start from the peak voltage and track the voltage values until you reach 90% of the repolarization level. This can be done by comparing each voltage value with the resting voltage level and determining when it reaches 90% of the difference between the peak and resting voltage.
- Note the time at which you reach the voltage value determined in the previous step. This represents the APD90, the time it takes for the action potential to reach 90% repolarization.
Keep in mind that this is a general approach, and the specific methodology may vary depending on the experimental setup or the model you are working with.
