El-Gamal, “Effect of diazinon, an organophosphate insecticide, on plasma lipid constituents in experimental animals

There has been increasing interest in studying the various effects of organophosphate insecticides in humans and experimental animals. Only a few data are available on the effect of the organophosphate insecticide, diazinon, on lipid metabolism. The aim of this study was to evaluate the effect of diazinon on plasma lipid constituents in mammalian animals. The plasma levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and phospholipids (PL) were measured in albino rats that were orally treated with a single dose of diazinon at a level of LD50 or with repeated daily doses at the levels of 1/2, 1/8, and 1/32 LD50 for 2, 8, and 32 days, respectively. After a 24 h post-treatment with a single LD50 dose of diazinon, TC was not significantly changed, the HDL-C and PL levels were significantly decreased, but the LDL-C and TG levels were significantly increased. Separate daily oral administrations of diazinon at 1/2 LD50, 1/8 LD50, and 1/32 LD50 doses resulted in a significant decrease in HDL-C and PL, with no significant change in TG. The LDL-C levels were significantly increased and TC showed no significant change with 1/2 LD50 and 1/32 LD50 doses of diazinon, whereas a significant decrease in the levels of TC, HDL-C, as well as LDL-C, was observed with the 1/8 LD50 dose. These data suggest that diazinon may interfere with lipid metabolism in mammals