As seen in some labs, people do hippocampal slices for their patch clamping on hippocampal neurons.
I was wondering what the significance is of making the hippocampal slices instead of using a more effort saving whole brain slice (with which I had successful patching for my CA1 neurons).
Thank you very much in advance.
Hi,
I guess it depends on whether it is important to keep the cortical input and output from the hippocampus or not for the experiment. Also if you remove any external structure you know that your responses may be rather coming from hippocampal activity and no external wiring is influencing them.
Hope that helped!
The difference is in the technique used to prepare the brain slices. Hippocampal slices (slices without other brain structures) can be prepared using a tissue chopper. In this technique both hippocampi are dissected out of the brain as intact pieces of tissue, and then chopped by dropping a razor blade through the tissue. The other approach, which is now more common I think, is to use a vibrating tissue chopper and cut sections through the whole brain. Since the hippocampus is not dissected first, the sections obtained from this approach usually contain other brain structures. You can then dissect the hippocampus out of the larger piece of tissue if it is more convenient. Both approaches yield good results in well-trained hands. You also may have better results for microscopic imaging if you use the vibrating tissue slicing method.
What you would like to study:1.- the answer of the hippocampal neurons ( in particular, pyramidal) by stimulation of cortical input - in this case you have to make whole brain sections ( using vibratome ): 2- response of hippocampal neurons after stimulation of nearby field - use the hippocampal slices (made by chopper)
As other's mention, it depends on your experimental goal. Acute brain slices is important to examine neuronal functions. We can use in vivo patch clamp technique to observe neuronal activity under the specific condition. However, as I know in vivo patch clamp approach is too hard. Therefore, using in vitro patch clamp, peoples are figuring out the function or property of the specific brain region or neurons.
People use the hippocampal slices when they want to look at only hippocampal neurons separate from other input. For treatments with an unknown, to ensure that the effect is at the hippocampus, hippocampal dissected slices provide a benefit.