Electrode Holders - Warner OC-725C User Manual

Setup

Electrode Holders

Voltage Electrode - The voltage recording electrode holder uses a silver wire for the
electrical coupling between the pipette and holder connector. Any silver wire contacting
the KCl solution in the pipette must be chlorided to reduce junction potentials (see
Chloriding Procedure in Appendix). The pipette should contain just enough KCl so that
approximately 1/2 inch of the chlorided wire is submerged. The pipette/holder assembly
is attached directly to the voltage headstage prior to mounting in a micropositioner.
NOTE: Do not fill the voltage holder with KCl solution.
Current Electrode - The electrode holder supplied for the current electrode also uses a
silver wire for coupling. In an manner analogous to the voltage electrode, the current
electrode wire must also be chlorided prior to assembly and use. The pipette/holder
assembly is mounted in a micropositioner with the mounting rod supplied.
NOTE: Do not fill the current holder with KCl solution.
Bath Probe
The bath clamp is designed to maintain a virtual ground in the oocyte perfusate. The
bath probe should be positioned so that the silver electrode wires can be inserted
into the recording chamber or into the agar bridge wells. Sticky wax or tape is usually
sufficient to secure the unit when positioned on a flat surface or, alternatively, the unit
can be held in place on a separate stand. The bath probe electrodes should also be
chlorided before use, as described above.
Electrode Placement and Grounding
Three drawings (shown on pages 19 and 20) have been included to illustrate the various
ways a bath circuit can be configured. Most applications involve only a single oocyte
and Figures A and B illustrate these setups. Figure C shows a setup for recording from 2
oocytes in a common bath with the use of dual clamps
NOTE: Cable routing must be performed with care. Bundle cables together
rather than routing them individually and keep them as far as possible from
sources of 50/60 Hz interference (e.g., line cords, transformers, etc.).
www.warneronline.com
21