I agree with most of what other folks have said concerning rodent tissue
processing.  However, I believe there is no getting around the fact that
animal tissue is drier than human, and must be soaked longer to section
properly.  There are tricks for sectioning, but after facing, our blocks are
usually soaked in a slurry of wet ice/water (with some Dove added) for at
least 30 minutes, and sometimes much longer.  Test changing your processing
or soaking times on stock tissues, but only change one variable at a time,
to see what happens to the tissues.  Good luck, keep trying!  What works
well in one lab may or may not work in yours.

Barb Munch
Supervisor, Histo/Necropsy
GlaxoWellcome

> -----Original Message-----
> From:	Cynthia Favara [SMTP:cfavara@niaid.nih.gov]
> Sent:	Thursday, November 18, 1999 12:31 PM
> To:	'J. A. Kiernan'; Philopena, Jennifer
> Cc:	'HistoNet Server'
> Subject:	RE: tissue processing (times; also clearing agents)
>
> John,
> 	Just a question in this regard. I attended a workshop about 4 years
> ago and the information given was that specimens could be over dehydrated,
> and that is why it is necessary to soak blocks. Now what I am apparently
> hearing is that it is not enough dehydration [ I was going to say
> underdehydration but don't know if that is a correct term] and this
> doesnot
> allow for adequate penetration of the remaining reagents. So if this is
> correct when a block has to be soaked inorder to be cut it is because the
> specimen has not been adequately dehydrated and increasing the processing
> time should help??? Have I got it right. Please let me know I would love
> to
> be able to do rodent spleen and liver without having to soak.
> Thanks,Cynthia Favara
> NIAID/RML/LPVD
> 903 South 4th Street
> Hamilton, MT 59840
> PH: 406-363-9317
> FAX: 406-363-9286
>
>