Temporal variations of the susceptibility of rats to liver damage by hexachlorobenzene

In this study, we examined some aspects of the chronotoxicity of hexachlorobenzene (HCB) on the liver of rats. Two series of animals received, daily, an oral dose of 16 mg of HCB kg−1 b wt in the beginning or at the end of the lighting phase. The treatment lasted 30 days under a 12L/12D photoperiod. The evolution of some enzymatic and metabolic indicators associated with histomorphological alterations is studied as measures of hepatocellular. The transaminase and Phosphatase alcaline activities appeared to increase significantly at the end of the light phase. Gamma glutamyl transferase (GGT) increased in the AM-treated group comparatively to its witnesses and to the PM groups.The rate of triglycerides presents a significant increase in PM-treated animals. These findings point out the elevated HCB toxicity for rats dosed near the end of their light/rest cycle, probably due to the feeding behaviour of this animal and provide additional support for the dosing-time influence of toxicants.