[Histonet] Russell-Movat's stain - again

[Nora Berghoff]

Hello everyone,

is there really nobody who is familiar with the Russell's modification
of Movat's pentachrome and who may have an idea as to what the problem
may be....?

Here is the problem (previous e-mail) again, just in case (I am not
giving up yet):

****
I have a question about Russell's modification of Movat's pentachrome
stain.
(Ref.: Russell, HK, "A Modification of Movat's Pentachrome stain", Arch
Path, Vol. 94, Aug 1972, 187-191)

I have been staining canine intestinal sections that have been fixed in
10% neutral buffered formalin, embedded in paraffin and cut at 5um.

The stain worked pretty well and gave good results for a while. Last
week I have had the following problem:

After destaining the crocein scarlet-acid fuchsin with 5%
phosphotungstic acid and then rinsing it in 0.5% acetic acid, it kept
destaining the tissue until everything was just very pale red (one slide
was completely destained - no red stain left whatsoever and the other
stains were pale as well). 
I always control the destaining under the microscope and stop when
there is still intense red color. 
The color kept coming off the slide in the acetic acid solution and
also in the following rinses in absolute alcohol.
I make the solutions (phosphotungstic acid and acetic acid) fresh right
before I need them. 

Does anyone have an idea what the problem might be? Is the acetic acid
not strong enough/the phosphotungstic acid too strong, etc?? Is it a pH
problem? 
****

As I previously said, I have tried to find an answer somewhere else
before bothering this e-mail list, but I simply can't find anything. And
I am afraid I am not experienced enough to detect simple errors that may
be obvious to someone else...
So if there is anyone who has even a vague idea of what may cause these
problems, PLEASE reply...My samples are very valuable, which is why I
don't want to keep staining (and then discarding) sections
unnecessarily, just hoping for the problem to resolve on its own.

Thank you!!!
Nora

Nora Berghoff
Research Assistant
Texas A&M University
College Station, TX