[Histonet] Cytoarchitectural analysis of axons and thick sectioning of neural tissue

[Patrick Laurie]

Dear histonet professionals,

 

My PI and I have been accumulating a large bank of 40 human brains and
spinal cords with ALS and controls with non-neurologic conditions.
Certain areas of the brain and the entire cord has either been fixed in
10% NBF and then processed through to paraffin or frozen for future
molecular studies.  My PI has been reading a number of papers, and
noticed that usually the brains are sectioned very thick (20+ microns).
I believe that I understand why, but I have tried to section our samples
that thick, and I have had a lot of problems.  Would it be easier with a
softer paraffin, (I am using Tissue-Tek's VIP brand), a different
microtome (maybe a sliding, or a vibratome) or some other method I
haven't considered.

 

Secondly, he wants to embed some of our spinal cord specimens in Epon
for cytoarchitectural analysis of the spinal tracts.  Typical procedures
I have seen require the tissue to be fixed in gluteraldehyde, mine are
fixed in formalin.  Are the two methods interchangeable, or could I
postfix in gluteraldehyde and then embed in epon?  

 

Thanks in advance for any tips.

 

 

Patrick Laurie, HT (ASCP)
Neurogenomics Laboratory
Benaroya Research Institute
1201 9th Ave
Seattle, Wa  98101
(206) 341-0681