Dr. Weber
EGFP is indeed stable in alcohol. But since you state that you're using OCT and frozen sectioning, I would cut the tissue then post-fix with formalin or whatever you usually use. I would not use eosin as a counterstain since it fluoresces in the range of dsRed. Liver may also give you a problem as it autofluoresces due to the endogenous porphryins. You may rather do immunohistochemistry with EGFP antibody or consult with the folks at Molecular Probes for quenching autofluorescence. Hope this helps, 
Donna Montague, M.S.
University of Arkansas for Medical Sciences
Department of Physiology & Biophysics and
Center for Orthopaedic Research
4301 W. Markham St. # 505
Little Rock, AR 72205