I am trying to do some DiI / immunocytochemistry double labeling for the
peptide vasotocin, and in our our first run we got no vasotocin signal.
we used tween 20 for tissue permeabilization (and didn't lose the diI
signal), but think we may need some kind of antigen retrieval because of
the long time the tissue sat in paraformaldehyde while the dye was
transporting.  does anybody have any experience / advice that might help
me out?

thanks
rick thompson