As an addition to Martin Wessendorf's list, there was a Science paper a number
of years ago that described a fluorescent Nissl in the FITC range. I believe
the primary ingredient was m-phenylenediamine. We tried it. It was easy to make
up. You could either stain the tissue, or just add the mix to the mounting
medium and in a day the tissue will be stained. In our hands, it stained all
the cells, but very strongly. We kept diluting to try and come up with a
non-overwhelming stain. So this is another alternative.
        I don't recall the year, but I believe the first author on the Science
paper was S. McConnell. Hope this helps.
        ANDREA ELBERGER
        Professor, Anatomy and Neurobiology
        The University of Tennessee, Memphis