Gayle,

In the context of formaldehyde fixation, it has long been known that certain
interactions, between tissues and formaldehyde, are freely reversible. The
shorter the initial fixation time the more rapid the reversal. This has
mainly been achieved by placing tissue in an excess of water following the
initial fixation. However, we have some evidence that ethanol concentrations
below 80% can also reverse some interactions if the fixation time is less
than 24 hours.
This reversal effect is mentioned in the following text books; Culling, the
latest Bancroft and Stevens, Pearse(1980) and Kiernan.

Regards

Bryan

> ----------
> From: 	Gayle Callis[SMTP:uvsgc@msu.oscs.montana.edu]
> Sent: 	April 18, 2000 1:06 AM
> To: 	histonet@pathology.swmed.edu
> Subject: 	an interesting question has come up
> 
> Have been a private discussion with someone, who brought up the point that
> fixation can reverse itself, and in the context of formalin?  but that the
> fixation process is eventually irreversible.   
> 
> Any comments on this, I found it interesting, and know the other party is
> looking in.
> 
> I have never experienced this, or even heard of it happening, but am
> always
> ready for enlightenment, could be something I have missed in reading,
> listening or discussion.
> 
> 
> 
> 
> Gayle Callis
> Veterinary Molecular Biology
> Montana State University
> Bozeman MT 59717-3610
> 406 994-4705
> 406 994-4303
>