Molecular Devices Axoclamp 900A, Руководство пользователя

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Setup and Tutorials
9. Connect the headstage from CHANNEL 2 to the ME2 input of the
CLAMP
‐
1U model cell and select the “Headstage 2, Membrane
Potential (10 mV/mV)” signal in the Channel 2 SCALED OUTPUT
section. The Channel 2 headstage will now serve as a cell membrane
voltage monitor. You should see that the Channel 2 SCALED
OUTPUT signal is identical to the Channel 1 SCALED OUTPUT from
Headstage 1 (100 mV
p-p
) as below. Channel 2 speed will be slightly
slower due to capacitance loading. You can speed it up by optimizing
Headstage 2 neutralization.
Figure 26. Monitoring the dSEVC voltage response with a second headastage.
IN0 is the membrane voltage as measured by Headstage 1 (dSEVC mode). IN1
is the membrane voltage as measured by Headstage 2 with 2.5 pF Pipette
Capacitance Neutralization.
Tutorial 4: Two
‐
Electrode Voltage Clamp (TEVC)
I. TEVC Using the CLAMP
‐
1U Model Cell
Two
‐
Electrode Voltage Clamp is preferred to discontinuous Voltage Clamp
(dSEVC) as it delivers a faster, lower noise and a more stable voltage
clamp. However, it requires two electrodes to be inserted into the same cell,
which is more difficult in smaller cells. Headstage 1 is always the “voltage
monitoring” electrode and Headstage 2 is always the “current
‐
passing”
electrode.
Equipment required:
CLAMP
‐
1U model cell.
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