Hexachlorobenzene, one of the most persistent
environmental pollutants, induces uroporphyria and
phospholipid alterations in rat liver. Harderian glands produce a secretion that is rich in
lipids and accumulate large amounts of
protoporphyrin. The aim of the present study was to determine if
hexachlorobenzene administration to rats affects
phospholipid and
porphyrin metabolisms in Harderian glands and if these effects are strain dependent. For this purpose, a time-course study (2, 3 and 4 weeks of
hexachlorobenzene treatment) of
phospholipid pattern and
porphyrin content was performed comparatively in two strains of rats (Wistar and Chbb THOM) which differ in their susceptibility to develop
HCB-induced
porphyria.
Hexachlorobenzene produced decreases in several
phospholipid contents, but no changes in
phosphatidylcholine levels. While the
sphingomyelin/
phosphatidylcholine molar ratio remained essentially constant until the third week in Chbb THOM rats, it showed a constant drop in Wistar rats, suggesting a more pronounced alteration of membrane fluidity in the later strain. In regard to
porphyrin metabolism, Wistar rats showed an increase in the
porphyrin content of the gland, while Chbb THOM animals showed a decrease. The study revealed that not only are the normal parameters of
phospholipid and
porphyrin metabolism in rat Harderian glands strain dependent, but the response to
hexachlorobenzene is also.