Richard-
 
Whenever I've worked with those plastics, there has always been a clearing
stage through acetone.  Since acetone would remove all non-bound fat, Oil
Red O would have nothing to go into.  
 
When I've worked with these plastics, I also did a post-fixation in osmium
tetroxide, which does a very good job of staining fats and lipid (it turns
them black).  Perhaps this would work for your purposes.
 
Joe

Joseph A. Saby, BA, HT(ASCP) 
Drug Safety Evaluation 
Pfizer Global Research and Development 
2800 Plymouth Road 
Ann Arbor, MI 48105 
Phone: (734)-622-3631 
FAX:   (734)-622-3866 
E-mail: joseph.saby@pfizer.com 

 

-----Original Message-----
From: RichardWHorobin@aol.com [mailto:RichardWHorobin@aol.com]
Sent: Thursday, May 17, 2001 2:49 AM
To: Histonet@pathology.swmed.edu
Subject: Re Oil red staining


Jaclynn Lett 
wrote: 



Has anyone used Oil Red O to stain lipids in tissues embedded in plastics 
(Epon or Epon-Araldite)?  If so, has this been done by staining en bloc or 
by staining the sections.  Sections would range from 1-4 microns in 
thickness.  



A couple of people so far have commented on how hard this would be, and our 
experience agrees with theirs. 
HOWEVER Jaclynn also said: 




We would also consider tissues embedded in glycol methacrylate.  We'd like 
to avoid frozen sections because we'd prefer the higher level of detail 
possible with plastic. 



In THAT case things look better! Would you settle for Sudan black, rather 
than Oil red staining of the lipid? If 'yes' then there is a method - which 
does indeed show even tiny droplets of lipid very clearly. This was worked 
out by the one-time king of GMA staining Peter Gerrits, and can be found in
J 
Neurosci Methods, as follows: 

     Gerrits PO, Brekelmans-Bartels M, Mast L, 's-GrAavenmade EJ, Horobin RW

and Holstege G. (1992).. 
     Staining myelin and myelin-like degradation products in the spinal 
cords of chronic experimental 
     allergic encephalomyelitis (Cr-EAE) rats using Sudan Black B staining 
of glycol methacrylate-embedded 
     material. 
     J. Neuroscience Methods. 45, 99-105 

Bye - Richard Horobin 

Institute of Biomedical & Life Sciences, University of Glasgow 
T direct 01796-474 480 --- E  RichardWHorobin@aol.com 
"What should we expect? Everything."