Hello!  I am working with a protocol for in-situ hybridization on mouse
brain that uses the following tissue prep:

-Whole brain is removed from mouse and immersed in 4*C 4%
paraformaldehyde and fixed overnight at 4*C.
-Tissue is then removed from fixative and immersed in 30% sucrose and
stored at 4*C until it sinks.
-Brain is then cut on cryostat at 15-20m.

The problem I am having is that when I cut the tissue and try to mount
it on slides, it won't lay flat, so it sticks to the slide quickly in
some places, and more slowly in others, leading to a very wrinkled
section.  The tissue works great as far as hybridization is concerned:
we do get a signal; but it looks terrible!  And the signal is
inconsistent because the tissue is all folded up, so some areas are
difficult to stain.

Does anyone out there have any suggestions as to how to mount the tissue
evenly?

Thanks for your help,

Stephanie Rodriguez
Primal, Inc.
Seattle, WA