Ultrastructure of vacuolated cells in the liver of rock sole and winter flounder living in contaminated environments

Abstract

Focal and diffuse areas of nonneoplastic vacuolated cells in the liver have been observed with light microscopy in up to 12% of the demersal rock sole (Lepidopsetta bilineata) inhabiting Eagle Harbor, which is a contaminated bay in Puget Sound. A similar type of liver vacuolation has also been observed at higher prevalences in winter flounder (Pseudopleuronectes americanus) inhabiting contaminated areas of Boston Harbor. This paper compares the ultrastructure of vacuolated liver lesions in feral rock sole with that of winter flounder from contaminated areas of Puget Sound and Boston Harbor, respectively.Rock sole from Eagle Harbor, Puget Sound, and winter flounder from Boston Harbor, were collected by bottom trawl from NOAA research vessels. Fish were killed and immediately necropsied. Adjacent pieces of tissue were collected for light and electron microscopy from grossly visible liver lesions or from the center of the liver. Samples collected for histology were fixed in Dietrich's solution, embedded in paraffin and stained with H&E.