Sex difference in enhancement of GGTase-positive foci by hexachlorobenzene and lindane in rat liver.

The ability of hexachlorobenzene and lindane in diethylnitrosamine (DENA) pretreated rats to enhance the incidence of gamma-glutamyltranspeptidase (GGTase)-positive foci was determined. In rats that received either DENA followed by a basal agar diet or hexachlorobenzene or lindane without prior administration of DENA, the incidence of GGTase-positive foci was negligible. When hexachlorobenzene or lindane were administered in the diet to rats that previously received a 2/3 partial hepatectomy prior to the DENA. The results suggest that hepatocarcinogenicity of hexachlorobenzene and lindane results from tumor promotion.