Effect of arsenic deprivation on phosphatidylcholine biosynthesis in liver microsomes on the rat

Beginning 2 days after breeding, pregnant Sprague-Dawley rats were fed either As-deficient (< 14 ng/g) or supplemented (2 .mu.g/g) diets throughout gestation, parturition and lactation. After weaning pups also were fed these diets. F2 and F3 generations were obtained by mating rats from different litters within each treatment group. Male rats from the F1 (age 71 days) and F3 (age 35 days) generations were used to ascertain the effect of As deprivation on phosphatidylcholine biosynthesis. At both ages, total liver microsomal protein was significantly lower in As-deprived than As-supplemented rats. In the rats aged 35 days, As deprivation depressed total liver microsomal phosphatidylethanolamine methyltransferase activity (nmol phosphatidylcholine formed/min per total liver). In the rats aged 71 days, As deprivation depressed significantly the specific activity (nmol phosphatidylcholine formed/min per mg microsomal protein) of phosphatidylethanolamine methyltransferase and total liver microsomal activities of phosphatidylethanolamine methyltransferase, phosphatidyldimethylethanolamine methyltransferase and choline phosphotransferase.