Sutter Instrument IPA Operation Manual page 58

58
[Tip: While a recording is in progress, the IPA amplifier can be switched into any
state (VC/CC). However, it is the researcher's own responsibility for maintaining
the health of the cell and interpreting the results from recording in mixed states.]
-
Output Units
Select the base unit of measurement for the output channel. This is set to 'V' for
voltage clamp experiments, and to 'A' (Amperes) for current clamp experiments.
Additional base unit types can be added to this list via the Preferences menu.
Note that the resolution of the unit is automatically adjusted in the signal.
Relative to Holding
If 'Relative to Holding' is enabled, the output signal is summed with the 'Holding'
level in the IPA Control Panel. If the Holding level is set to '0', this setting has no
effect.
This provides an alternate way to construct and edit stimulus waveforms, as
relative to the holding level, when this is more convenient for your experiments.
Return to Holding at Sweep End
Use the holding level as the output signal when the system is not acquiring data,
i.e. the "down time" after the Waveform/Acquisition Duration ends, but before the
the next sweep starts (a minimum of ~100 ms per sweep).
This ensures that your cells are kept in a resting state as much as possible, and
that each output sweep starts from the same amplitude (holding) level.
Enable P/N Leak Subtraction
If endogenous leak conductance is an issue with your seal, configure the "P/N" leak
subtraction waveform settings per output channel
Note that this section is dependent upon the 'Enable Acquisition of Leak Pulses'
setting in the Acquisiton & Routine Parameters section.
Preview Leak Pulses
Display the leak subtraction pulses in the Routine Editor waveform preview
panel. A leak subtraction "pulse" is a scaled copy of the main stimulus
waveform.
Alternating Leak Polarity
You can reduce directional bias in the leak conductance by alternating the
polarity of the leak subtraction pulses on a sweep-by-sweep basis, as long as
no ion channels are activated.
Num Leak Pulses
Set the number of leak pulses used to average out noise and leak
conductance. Adjust this number in accordance with the amount of noise in
the signal. With the precision of modern 16-bit digitizers, this number can
sometimes be reduced to less than 4 leak sub-pulses.
INTEGRATED PATCH AMPLIFIER OPERATION - M – R . 1.0.6 (20160729)
ANUAL EV