Dear Susan  I have done a lot of NADPH stains and i think that it is not
stable in Xylene so i use glycerol gelatine  as mounting media...my
experience is that they appear to break down after a few weeks  but stuff
mounted in glcerol gel is good 5 years on...hope this helps Mary

On Fri, 18 Feb 2000, Susan Travers wrote:

> I am writing to ask if anyone has seen and has a solution to an artifact 
> that we have seen in our NADPHd material.  It appears as a small, elongated 
> crystalline precipitate that appears to be on the surface of the tissue. 
> Our technique for doing the NADPHd is the standard one using .1% bNADPH & 
> .01% nitroblue tetrazolium in PB. The only twists are: that the tissue is 
> fixed with PLP , and we double-label the tissue using DAB 
> immunohistochemistry (first NADPHd, then ICC)
> 
> We have tried to trouble shoot by (1) filtering the staining solution-- no 
> help, (2) doing the reaction in the dark (inconvenient and no help), (3) 
> exploring the effects of using ETOH to dehydrate or not-- this is 
> interesting-- with ETOH, which is our standard procedure the artifact looks 
> crystalline, without ETOH-- looks like very small spherical globules, (4) 
> using xylene or HEMO-D to clear-- no effect, and (5)coverslipping with 
> permount versus cytoseal (no effect).
> 
> The only other hints are that we never see the artifact on wet, 
> uncoverslipped sections, and occasionally it seems that the artifact gets 
> worse the first few days after coverslipping; also the artifact does seem 
> worse in the double-labeled tissue.
> 
> Any advice would be greatly appreciated.
> 
> 
> 
> 'Regards,
> Susan Travers 
> 
>