Effects of dietary levels of protein and fat on DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) and liver lipid metabolism.

Abstract

In order to examine the effect of dietary protein and fat on DDT metabolism and liver lipid concentration, rats were supplied with calory adjusted diets consisting of various amounts of protein and fat. The results suggested that dietary protein and fat changed the liver lipid concentration. They also showed that dietary protein and fat affected the residual concentration of DDT and its metabolites in the liver and adipose tissue. The change of the concentration of lipids in liver accompanied a change of the residual concentration of DDT in liver. This fact indicates that one effect of dietary protein and fat on the metabolism of DDT is attributable to the metabolic change of lipids in liver. Dietary protein accelerated the metabolism of DDT and reduced its residual concentration in liver. The results suggest that regression equations exist between the residual concentration of DDT in liver and (1) dietary factors and (2) lipid concentration in liver; In (DDT) = a x 1n (x1) + b x 1n(x2) + c x 1n(TL) + d (1) In(DDD or DDE) = a' x 1n(TL) + b' x 1n(PL) + c' (2) where x1, x2, TL, and PL are the dietary protein, dietary fat content, total lipid, and phospholipid concentration in liver, respectively. a, a', b, b', c, c', and d are constants. The concentrations of DDT and its metabolites estimated from equations (1) and (2) agrees well with the measured concentrations in liver.