Multichannel Systems HiClamp Manual - Manual (Page 32)

HiClamp Manual
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5.4 Selecting Oocytes for TEVC Recording
Selecting Oocytes
Please read chapter "Preparation of Oocytes" in Service and Maintenance.
Plating Oocytes
Please read chapter "Plating Oocytes" in Service and Maintenance.
Loading the oocytes plate
Place the 96 microtiter plate containing the oocytes in the right slot on the table.
Tighten the fixation of the plate (lower right) and verify that the holding screw is properly
secured. Poorly fixed oocyte plate can cause movement of the plate and result in a basket crash,
or other dysfunction of HiClamp.
5.5 Starting a Recording Sequence
A program sequence is a chronology of operations that are executed sequentially according to
a set of icons that are stored in the program sequence. Each icon symbolizes a fixed procedure,
for example loading the oocyte or setting up the amplifier. Please see chapter "Icons and
associated Effects" below. Each icon contains a given set of information to execute the desired
actions. For example, the "Oocyte" icon symbolizes the type of message injected into the oocytes,
the number of cells available etc. At difference, the icon corresponding to the amplifier will store
the information controlling the amplifier gain, filter conditions, voltage clamp set up, voltage
steps etc. To access the content of a given icon the user double click on the icon stored in the
program sequence. The first and simplest example presented below illustrates such procedure.
5.5.1 A first and simple example
The simplest example would be to test how oocytes are expressing membrane proteins and,
in the case of ligand gated channels, would consist at measuring the amplitude of the current
evoked by a brief pulse of agonist. To execute such operations it is necessary to first load an
oocyte into the recording basket, impale the electrodes, and apply the agonist while recording
the data.
The icons sequence above presents such a sequence. To prepare this sequence one icon at
a time is selected from the tools by a single click on the desired icon. Following the assembly
of such sequence it is now necessary to store in this HiClamp sequence the properties including
the type of message injected into the oocytes (mRNA or cDNA injected), the number and position
of the oocytes in the feeder plate, the solution that is applied and for how long, the holding
potential etc.