The effect of 28-day pesticide feeding on serum and tissue enzyme activities of rats fed diets of varying casein content

Abstract

Female and male rats were fed diets containing 19, 8, or 3% casein with either no pesticide or with pesticides at various concentrations for 28 days. In rats of both sexes fed diets with no pesticide, the liver triacetinesterase (AliE) activity was related to the amount of casein consumed. The serum cholinesterase (ChE) activity of females was also decreased with decreasing dietary casein but in males was reduced only in those fed the 8% casein diet. Serum AliE activity was optimal at 8% and 3% dietary casein. ChE activity in brain, β -glucuronidase ( β -Glu) activity in serum, and aniline hydroxylase activity in liver were the same at all casein levels. The activity of p -nitroreductase was reduced at lower dietary casein levels. In the pesticide-treated group, chlordane-induced increases in liver AliE, aniline hydroxylase, and p -nitroreductase activities were dependent upon pesticide dose. Increases in serum AliE activity were dependent upon both pesticide dose and casein intake. Chlordane reduced serum β -Glu more at 8% than at the 19% casein level. Parathion-induced inhibition of serum ChE, serum and liver AliE, and brain ChE increased with increasing dose and with decreasing casein content. Parathion increased serum β -Glu activity to the same degree at all casein levels. Banol-induced inhibition of ChE in the serum was pronounced at low casein levels. The increase in serum AliE by Banol followed the decrease in casein levels; inhibition of liver AliE was independent of casein intake and was dose-dependent. Banol did not affect β -Glu.