Freezing or paraffin embedding tissue shatters the cell membranes.
Cytosol leak out of cells.  However, if you tried to advance a microtome
blade straight into unfixed tissue, the soft tissue would just push back
and distort.  The oscillating blade of a vibrating microtome gently saws
its way into the tissue, allowing sections without steps to harden the
tissue for cutting.

HRP and immuno reactions (particularly if cytosol proteins are sought)
are stronger and give better stained slides if the tissue is cut on a
vibrating microtome.  Also, live tissue can be cut, as for brain slice
studies in rats, or perhaps clinical biopsy material, with a Vibratome.
The downside is that you can't get fixed sections thinner than 20
microns, or fresh sections thinner than 50 microns, without great care.

  


Cordially,

Charles W.  Scouten, Ph.D.
myNeuroLab.com
5918 Evergreen Blvd.
St. Louis, MO 63134
Ph: 314 522 0300  
FAX  314 522 0277
cwscouten@myneurolab.com
www.myneurolab.com


-----Original Message-----
From: Morken, Tim [mailto:tim9@cdc.gov] 
Sent: Thursday, March 21, 2002 10:19 AM
To: 'Histonet'
Subject: What are vibratome sections used for?

Just wondering, I've seen vibratomes for years but never really
understood
what people are using them for. Anyone?

Tim Morken
CDC, Atlanta