Metabolic changes following oral exposure to tetrachloroethylene in subtoxic concentrations.

Mice were exposed to very small quantities of Per (0.05 and 0.1 mg Per/kg body weight per day) administered orally for 7 weeks. It was shown that Per was transported through the body by two separate mechanisms and was finally stored in the adipose tissue. On the one hand, Per reaches the interior of the membranes of red blood cells, leading to changes in the entire erythropoietic system. The membranes of the red blood cells are destroyed prematurely and its fragments are increasingly phagocytized in the spleen. The result is a high level of Per stored in the spleen. The increase in haemolysis was also demonstrated by showing an increase in LDH activity and the accumulation of haemosiderin in the macrophages in the spleen. Only 8 weeks following discontinuation of Per, these changes were reversible. On the other hand, Per is also transported with the chylomicrons. Since the lipoprotein lipase is inhibited by Per, these molecules are broken down to a lesser degree. The concentration of triglycerides (the major component of the chylomicrons) in the serum was elevated, and the chylomicrons were increasingly integrated into the adipose tissue, Per also reached this depot fat. It took as long as 16 weeks after discontinuation of Per until these changes were fully reversed and the experimental mice no longer differed from those in the control group.