[Histonet] quiq decalcifier

[gayle callis]

Ben, 

Please clarify what you mean here and what species you are working with.
Are you working with mouse heads with skull and whole brain intact?  Or are
there residual skull fragments or the does the brain contain some calcified
areas (latter is something I personally have not experienced or heard of??)
Unfortunately, quick decalcification may not be a choice but one can choose
a decalcifying agent that is more rapid than others.  HCL, commercial
products are very rapid while formic acid is generally slower and more
gentle.  One can adjust acid concentrations to increase speed.  If you want
a quicker decalcifier, I suggest any rapid HCL available from Thermo, VWR,
Surgipath, Richard Allan, or even RDO (very strong and fast HCL decalcifying
agent).  

I am taking some guesses here, but maybe these suggestions are what you
need. 

We have done formalin fixed whole mouse and rat skulls, after removing ears,
and skin for 7 to 10 days, then decalcified these with 15% formic acid using
an endpoint determination to know when calcium is gone.  The paraffin
processing schedule was extended considerably. Results were excellent for
whole skull 5 um skull sections stained with H&E. We could do cross sections
from front of nose to back of skull OR mid sagittal from one side of skull
to other, semi-serial sections.  The latter gave us the best view of what we
were looking for in the nasal turbinates.  Although we were more interested
in the bone, the brain was well preserved, and well stained.  

If you have residual calcifications in your embedded sample, simply face the
block and put the block face down in a decalcifying solution for 15 minutes
or so (formic acid or HCl) then rinse well to get rid of acid, recool block
if needed, return to microtome and section.  Be sure to NOT retrim the block
face, as you need to access the first few sections that come off the block,
as block face decalcification only penetrates a few um.  

Good luck from an Old Bonehead, and hope these SUGGESTIONS help you. 

Gayle M. Callis
HTL(ASCP)HT,MT
Bozeman MT 59715

 
--- On Thu, 1/29/09, Ben Spirto <brod033 <@t> gmail.com> wrote:

From: Ben Spirto <brod033 <@t> gmail.com>
Subject: [Histonet] quiq decalcifier
To: Histonet <@t> lists.utsouthwestern.edu
Date: Thursday, January 29, 2009, 12:20 PM

Could someone tell me the best way for quick decalcification of parafin
embeded brain tissue. I know about treatment with HCl. Anything else? With
something, perhaps that can be found in the biochemical lab??? thanks

Ben