Hi Christian:
It's always a pleasure to read you here. Thank you very much for your
nice comments. Just a short question regarding your comments.
What did you mean with "We used an Axoclamp 2B. As far as I understand
that's acutally an overkill"? I read quite a few good papers, where they
used exactly this amplifier without any extra consideration.
Thank you very much in advance.
Christian Wilms wrote:
> Hi Thomas and Segundo!
>> I've only done extracellular recording for a couple of days in a sommer
> course two years back, but I just grabbed my old notebook and found some
> of the information you guys are looking for. Maybe it turns out to be a
> of help for you:
>>>> > 1. What properties should the electrode have (compared to a
>> > conventional patch electrode e.g. resistance, shape, filling etc.)?
>> We used glass pipettes filled with 2M NaCl. With this solution the
> pipettes we used averaged around 10MOhms.
>>>> > 2. Do I have to use a different headstage?
>>>>I don't think so. There're headstages specific for extracellular
>>recordings, but I think those used in patch-clamp could work.
>> As far as I remember we used the same headstage for patching and for
> extracellular recording.
>>>> > 3. Can I use my usual patch amplifier (Axoclamp 2B)?
>> We used an Axoclamp 2B. As far as I understand that's acutally an
> overkill. I'm know of one lab that uses self-built amplifieres for
> recording extracellular signals in cerebellar slices. For those of us
> who are less inclined to build one, there are fairly simple
> field-potential amps to be had for relatively little money (the EXT
> module series from www.npielectronic.com for example).
>>>> > 5. Where to place the electrode (deep in the tissue or superficial)?
>> THAT is the big question. It depends on what you want to see. The idea
> of current sinks and current sources is very central to understanding
> the whole concept of extracellular recording. There is a well written
> and informative chapter on this stuff to be found in:
>> "Foundations of Cellular Neurophysiology" (Bradford Books (Hardcover))
> by Daniel Johnston and Samuel Maio-Sin Wu
>> A personally believe that to be a very good starting point. Maybe some
> of the more experienced electrophysiologists in this group have some
> more to say on this.
>> Regrads, Chris
--
ÿþS