[Histonet] Movat's stain/hematoxylin

[Nora Berghoff]

Hello everyone!
 
I am new to this list, so first I would like to say hi to everyone!! I
have been reading the archives and find that they are a wonderful source
of knowledge!
 
I am also new in the world of histology - which is why I am asking for
your help:
I want to stain canine intestinal biopsies for collagen using Russell's
modification of Movat's pentachrome stain. I have stained my first
sections today and have encountered some problems:
 
First, most of my muscle tissue is not really red, but rather
orange/yellowish from the saffron, as it seems. But some areas of muscle
have stained red. 
Fibrin does seem to be stained well (if what I have identified as
fibrin is in fact fibrin...;)) 
 
What can cause such irregular staining?  How long after cutting of the
sections are they "stable" (meaning they don't lose any staining
ability) on the slide?
Could it be that my cut sections are old and "dried out"? I have had a
histo lab embed and cut them, which is about five weeks ago...so I
figured something may have happened to the sections in the meantime?
 
Also, my elastic fibers and nuclei are not really black (I stained them
according to the protocol for 15 minutes in hematoxylin sol.). I found
it difficult to find the right hematoxylin (there are so many of them!),
so maybe I have the wrong one after all...
 
Does anyone know how long the individual staining solutions are stable
after preparing them? Maybe my solutions are bad...
 
So many questions and "maybe's" - I would really appreciate it very
much if I could get some suggestions on any of them!
 
Thank you so much in advance!!
 
Nora Berghoff
 
Research Assistant
Gastrointestinal Laboratory 
Dept of Small Animal Clinical Sciences
College of Veterinary Medicine
Texas A&M University