Vector sells Vectashield with DAPI already in it.  Not too long ago,
someone talked about using this to stain the nuclei to provide contrast
with another fluorescent marker.  It is compatible with alcohol or formalin
fixation and unfixed tissue sections, cell cultures??

Caveat here:  if DAPI stains the DNA or both live and fixed cells, it will
"light" up your skin DNA!  Wear gloves when working with this dye, and
protect from DAPI dust floating in air when weighing it out. Sigma sells it   

Access this publication for methods and material on staining with a DAPI
rather than use the DAPI/Vectashield mounting media:

Tarnowski, BI et al, DAPI as a useful stain for nuclear quantitation
Biotechnic and Histochemistry, 66(6):296-302, 1991

Good luck
Gayle Callis
Veterinary Molecular Biology
Montana State University
Bozeman MT 59717-3610
406 994-4705
406 994-4303