Cracked Rat Livers

From:Histo-Scientific Research Laboratories

Dear Silvia,

This artifact is a phenomena that research labs see fairly often with liver
tissue.  We are primarily an animal research facility that deals with a
variety of species from fish to primate and have dealt with this problem in
a variety of ways.  Chances are, your processing had nothing to do with this
problem.  When we see this dry/cracking artifact we call for a recut of the
block on both a regular slide, and a superfrost plus slide.  NEVER put
livers in an oven to dry (that goes for all tissue in my opinion!).  Allow
slides to dry overnight at room temp and stain the slides.  If the recut
slides have this artifact, e will then ask our gross trimmers to go back and
give us another representative sample of liver- then we will process as
normal.  Many times this re-trimmed liver is fine.  Most of the time there
is livers that are cracked and some that are beautiful from the same
processor telling me that it is not a processing problem.  We attribute this
problem to the following areas:  1)  Sometimes the livers of any given
animal are ill.  ).  The fixative used and/or length of fixation.  3)
Necropsy technique plays an important role in fighting artifact of any kind.
For instance, if the animal died on a Friday night and was not necropsied
until Monday morning the bile will have damaged the liver for sure.  4) And
lastly, the amount of time the gross trimmer allowed the tissue to sit on
his bench.  If he had a liver out on his bench exposed to the air and went
to lunch, that liver might as well be thrown away.  I hope these suggestions
help.

Sincerely,

Tom Galati
Histology Laboratory Director
HSRL- A GLP Compliant Laboratory
137 S. Main Street
Woodstock, VA  22664
www.hsrl.org
tomgalati@hsrl.org
(540)459-8211
fax: (540)459-8217
----- Original Message -----
From: "Pasquetto, Silvia (by way of Histonet)"

To: 
Sent: Friday, September 21, 2001 10:04 AM
Subject: Technical problems


> Dear all,
> in the last days there were problems with computer network in our company
> and so I would forward you a message that I have wrote three days ago.
> Forgive me if you have received this post twice...
>
> Regards
> Silvia Pasquetto
> GSK Company
>
> PS. Today I have stained the slides processed with a shorter program
(please
> find enclose details below) but I find some "interesting" artefacts
> consisting in perfect rounded extracellular vacuolization (I hope this
word
> exist!) of hepatocytes around the centrolobular vessels.
>
> New processation lenghts
> 1) formalin
> 2) ethanol 70% 1 hour at 35°C with p/v cycle
> 3) ethanol 95% 1 hour at 35°C with p/v cycle
> 4) ethanol 100% 45 minutes (instead of 1 hour) at 35°C with p/v cycle
> 5) ethanol 100% 45 minutes (instead of 1 hour) at 35°C with p/v cycle
> 6) ethanol 100% 45 minutes (instead of 1 hour) at 35°C with p/v cycle
> 7) ethanol 100% 1 hour at 35°C with p/v cycle
> 8) toluene 45 minutes (instead of 1 hour) at 35°C with p/v cycle
> 9) toluene 50 minutes (instead of 1 hour) at 35°C with p/v cycle
> 10) toluene 1 hour at 35°C with p/v cycle
> 11) wax 45 minutes at 58°C with p/v cycle
> 12) wax 45 minutes at 58°C with p/v cycle
> 13) wax 45 minutes (instead of 1 hour) at 58°C with p/v cycle
> 14) wax 1 hour at 58°C with p/v cycle
>
>
> Any suggestions or comments are greatly appreciated
>
> -----Original Message-----
> From: Pasquetto, Silvia
> Sent: martedì 18 settembre 2001 17:28
> To: 'histonet@pathology.swmed.edu'
> Subject: Technical problems
>
> Hi guys!
> I need all you for some technical problems regarding liver slides
> preparation. I work with animal (rat) tissue.
> Recently, I have processed some pathologic (i.e. oil red o' staining
> revealed fatty accumulation) rat liver and I was amazed when after
> processing, cutting and staining of these samples there were some cracks
in
> tissue under microscopical observation. The appearance is similar to the
> fissures in the dry land: I hope that comparison is clear for you! I think
> there is a correlation between this appearance and the length of
> processation of these sensitive livers. What do you think about this?
> Tomorrow I have tried to reduced the lenght of  ethanol absolute, toluene
> and wax staying. Please find below the details of the first processation
> that gave me this problem.
>
> 1) formalin
> 2) ethanol 70% 1 hour at 35°C with p/v cycle
> 3) ethanol 95% 1 hour at 35°C with p/v cycle
> 4) ethanol 100% 1 hour at 35°C with p/v cycle
> 5) ethanol 100% 1 hour at 35°C with p/v cycle
> 6) ethanol 100% 1 hour at 35°C with p/v cycle
> 7) ethanol 100% 1 hour at 35°C with p/v cycle
> 8) toluene 1 hour at 35°C with p/v cycle
> 9) toluene 1 hour at 35°C with p/v cycle
> 10) toluene 1 hour at 35°C with p/v cycle
> 11) wax 45 minutes at 58°C with p/v cycle
> 12) wax 45 minutes at 58°C with p/v cycle
> 13) wax 1 hour at 58°C with p/v cycle
> 14) wax 1 hour at 58°C with p/v cycle
>
> In your opinion which is the correlation between this troublesome effect
and
> the fatty accumulation in the liver?
> Any suggestions or comments are greatly appreciated
>
> Thanks in advance
> Silvia Pasquetto
>
>
>
> Silvia Pasquetto
> Safety Assessment dept.
> GLAXOSMITHKLINE
> Tel. +39 +45 921 8111
> Int. 4735
> sip95711@gsk.com
>
>
> Silvia Pasquetto
> Safety Assessment dept.
> GLAXOSMITHKLINE
> Tel. +39 +45 921 8111
> Int. 4735
> sip95711@gsk.com
>
>
>






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