Multichannel Systems HiClamp Manual - Manual (Page 62)

HiClamp Manual
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Placing the crosshair (in the crosshair mode) immediately at the end of the capacitance discharge
and at the end of the voltage step allows a first estimation of the current activated by the voltage
step. Ideally, measurement of the current should be subtracted from the current passing through
the passive properties of the membrane which is usually obtained by subtracting the current
measured for the same voltage step in presence of a selective blocker.
Positioning the crosshair for KV1.4 activation
After setting the crosshair at the desired position the selection of the calculator is made and
the appropriate sequence step is selected by a single click. The number corresponding to the
step is displayed in the calculator window and results are readily obtained by selecting the
potassium IV button. The window displaying all the IV curves measured in different oocytes
is displayed and the desired IV can be displayed separately by selecting the appropriate graph.
The current-voltage window displaying the voltage activation curve is displayed.
Current-Voltage activation curve for KV1.4
A plot of the corresponding conductance can be obtained by pressing the button “conductance”
and setting the appropriate reversal potential for the considered ion (-80 mV in our example).