[Histonet] methyl green counterstain

[Jacqui Detmar]

Hi all.  I am doing some immunohistochemistry and TUNEL staining on mouse placental tissue.  I have noticed that my methyl green counterstain on placentae assayed for TUNEL looks normal, but when I apply the same steps to tissue from the same block, but exposed to immunohistochemistry, the methyl green counterstain is very weak, bleaches out quickly during dehydration and generally looks pretty crappy.  The methyl green recipe I am using is as follows:  0.5% methyl green in 0.1M sodium acetate buffer, pH 4.2.    I would like to emphasize that no matter how quickly I dehydrate with the IHC sections, the colour is still very dim.  

The reason I am using methyl green is b/c I am doing IHC for nuclear proteins (Ki67, etc.) and don't want to use hematoxylin, since it's a little dark.  Any suggestions?

Thanks,

Jacqui Detmar