Greeting,

I have had the unusual occurrence of having the "white matter" in the
brains of monkeys and now rats strongly stain with a Nissl stain (Cresyl
violet or Neutral red).  These brains have already been through a lot:
the monkey brains were frozen sections while the rat were 4%
formaldehyde fixed and both types of sections were given at least 1
immunostain before Nissl staining.  The problem is that occasionally the
white matter will pick up the Nissl stain and will not let go in spite
of repeated washes with graded alcohol (70-95%) and the 95% + 0.1%
Acetic acid.

The actual Nissl staining of the cortical tissue is OK.  The cortical
cell layers are where they should be and look good.  The question I have
is why the heck does this happen occasionally.  I guess more
importantly: How can I prevent this from happening again?

TIA
____________________________________________
Bret A. Morrow, Ph.D.
Associate research scientist
Associate clinical professor
Yale University School of Medicine
New Haven, CT 06520-8066

voice 203.785.4515
fax  203.785.7670
email  bret.morrow@yale.edu