Acute exposure of rhesus monkeys to dieldrin: effect on lipid metabolism

Endrin-induced histopathological changes and lipid peroxidation in livers and kidneys of rats, mice, guinea pigs and hamsters

Endrin toxicity may be due to an oxidative stress associated with increased lipid peroxidation, decreased glutathione content, and inhibition of glutathione peroxidase activity. Extensive interspecies variability exists in sensitivity towards endrin. Therefore, histopathological changes and lipid peroxidation in the livers and kidneys of rats, mice, hamsters, and guinea pigs were examined 24 hr after the administration of 4 mg endrin/kg body weight orally in corn oil. Degeneration and necrotic changes with inflammatory cell infiltration were observed in livers and kidneys, and interspecies variability occurred. Fatty changes in the form of hepatic foam cells with cytoplasmic vacuolation were present. Lipofuscin pigments, associated with lipid peroxidation, were observed in hepatocytes and Kupffer cells. These histopathological conditions were prevented in rats which had been pretreated with butylated hydroxyanisole, vitamins E and C, or cysteine, antioxidants and free radical scavengers which have previously been shown to inhibit lipid peroxidation. The extent of endrin-induced lipid peroxidation correlated well with the degree of histopathological changes. Thus, histological changes consistent with the induction of an oxidative stress were observed following the administration of endrin to various animal species.

Effect of acute sublethal and chronic administration of DDT (chlorophenotane) on brain lipid metabolism of rhesus monkeys

Either a single oral dose of 1,1,1-trichloro-2,2-bis-(p-chlorophenyl) ethane (DDT), 150 mg/kg body weight or a long-term chronic dose of the pesticide, 10 mg/kg body weight daily for 100 days was administered to rhesus monkeys and the level of various lipid classes was studied in the brain. A significant decrease was observed in total lipid, unesterified cholesterol and phospholipid (PL) level. Individual PL fractions showed a generalized pattern of reduction, so also did the cholesterol (chol)/PL ratio. Sphingomyelin (SM) registered a significant increase, while no significant alteration was observed in the brain galactolipid and ganglioside level. Lipid lowering effect of DDT was more pronounced in the chronic group. Lipids associated with the myelin sheath were found to be more resistant to pesticide injury, while cholesterol and PL metabolism were more affected.

Effect of dieldrin injection on the level of certain amino acids and some enzymes in rat brain

The present investigation revealed the effect of the organochlorine insecticide dieldrin at the dose level 0.25 LD50 at different time intervals on the concentration of 11 rat brain amino acids, on the activities of glutamic oxyacetic transaminase (GOT), glutamic pyruvic transaminase (GpT) and cholinesterase. The study was also extended to include the total protein content during the tested periods. The daily injection of dieldrin caused a marked decrease in the levels of glutamic acid, glutamine and taurine and an increase in the levels of aspartic acid, asparagine, GABA, glycine, lysine, serine, alanine and histidine. However, the maximal increase and decrease were recorded for most of the tested amino acids at the end of the tested period. The activity of the transaminases increased significantly. The recorded values of GOT were usually higher than GPT. Cholinesterase activity was inhibited thoroughly during all the experimental periods. Total protein content was decreased in the experiment; the minimal value was given 3 days after the injection.