Response of epithelial cell lines from the rainbow trout gut and gill to ammonia.

Rainbow trout epithelial cell lines from the gill, RTgill-W1, and gut, RTgutGC, were exposed to NHCl at 18-21 °C in L15 (basal medium) with fetal bovine serum and were found to undergo cytoplasmic vacuolization and cell death, depending on NHCl concentration and exposure time. Vacuolization arose within 24 h of cultures being exposed to 10-100 mM NHCl, and vacuoles disappeared over 24 h after NHCl-exposed cultures were returned to just L15/FBS. RTgill-W1 appeared more sensitive to vacuolization, with one indicator being the maximal proportion of vacuolated cells in a culture, which approached 100% in 50 mM NHCl for 72 h.