STAGES OF HYDROPIC VACUOLATION IN THE LIVER OF WINTER FLOUNDER PLEURONECTES-AMERICANUS FROM A CHEMICALLY CONTAMINATED SITE

Hydropically vacuolated hepatic epithelia are abnormal cells prevalent in winter flounder from chemically contaminated habitats. These cells often have been associated with certain hepatic neoplasms. Here we de fine the 3 stages of the lesion and show an age and length-specific pr ogression of each stage. The first cells to undergo vacuolation are ce ntrotubular preductular cells. Intermediate stages involve entire hepa tic tubules, and advanced stages consist of grossly visible foci of va cuolation that often encapsulate neoplastic foci. Vacuolation was foun d in fish from Boston Harbor, Massachusetts, USA, that were maintained on clean food and in clean water for 5 mo. These data are consistent with vacuolation being a persistent condition. The early involvement o f preductular cells, possibly oval cell equivalents, the likely persis tence of hydropic vacuolation after chemical exposure, and the close a ssociation of vacuolation to neoplastic foci, are consistent with sugg estions that vacuolated cells may be Linked to hepatocarcinogenesis in these fish. Definition of 3 distinct stages of hydropic vacuolation s uggests that the prevalence of each lesion stage may reveal temporal a nd spatial trends in environmental health in winter flounder and possi bly other fishes.