aldrin and Liver-Diseases

Cytochrome P-450 dependent monooxygenases play a dual role for xenobiotic metabolism. On one hand they initiate the primary rate limiting step for the elimination of a bulk of drugs and organic chemicals. On the other hand they catalyze the formation of toxic metabolites from chemical carcinogens and many other toxic chemicals. Numerous studies have shown that their activity in animals is subject to the influence of various modifying factors, such as strain, species, sex, age, diurnal rhythm and the effect of enzyme inducers. Less is known about the influence of these factors on human cytochrome P-450 enzymes. Here we report the results of an extended study on human liver cytochrome P-450 performed with liver biopsies of 178 individuals taken for diagnostic purposes. The enzymatic activity was determined by the aldrin epoxidase assay indicating a variety of enzymes inducible by phenobarbital and by glucocorticoid and androgenic hormones. The frequency histogram of individual aldrin epoxidase activities showed a unimodal distribution and a variation factor of 100 between maximal and minimal activity. Individuals with severe liver diseases, such as cirrhosis and fatty liver, exhibited a 50% loss of enzyme activity. Age and sex did not significantly influence the enzyme activity. No significant correlation was observable between the rate of aldrin epoxidation and debrisoquine 4-hydroxylation, a prototype of a genetically controlled cytochrome P-450 reaction. We assume that the broad interindividual variation of epoxidase activities is more likely due to the influence of exogenous and endogenous inducers rather than to a genetic polymorphism.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Aldrin; Cytochrome P-450 Enzyme System; Enzyme Induction; Female; Humans; Liver; Liver Diseases; Male; Middle Aged; Mixed Function Oxygenases; Polymorphism, Genetic; Sex Characteristics

The development of hyperplastic and neoplastic lesions of parenchymal cells of the liver adjacent to central veins was observed in C3H mice ingesting the chlorinated hydrocarbons, dieldrin or aldrin, in the diet. Lesions could be followed from pericentral hyperplasia to areas of hyperplasia, nodules of hyperplasia, small hepatocellular carcinomas, and large well-developed carcinomas, occasionally with metastases. Sometimes pericentral hyperplasia was diffuse throughout most or all of one lobe of the liver. These hyperplastic cells collided to become one large nodule and also one large carcinoma. The carcinomas were well-differentiated or moderately well-differentiated and grew on transplantation to isologous hosts. Histologically, the hyperplastic cells adjacent to central veins were increased in size, frequently with double nuclei. Carcinoma cells varied in size and shape and were huge with large nuclei, prominent nucleoli, and eosinophilic cytoplasm. Similar hepatocellular carcinomas were seen previously with carbon tetrachloride, another organochlorine chemical.

Topics: Aldrin; Animals; Carcinoma, Hepatocellular; Chemical and Drug Induced Liver Injury; Dieldrin; Female; Hepatic Veins; Hyperplasia; Liver Diseases; Liver Neoplasms; Male; Mice; Mice, Inbred C3H

Topics: Adipose Tissue; Aldrin; Animals; Chlordan; DDT; Dieldrin; Dogs; Drug Synergism; Endrin; Environmental Exposure; Estrus; Female; Fertility; Food Deprivation; Humans; Hydrocarbons, Halogenated; Lactation; Liver Diseases; Male; Mice; Neoplasms; Pesticides; Pregnancy; Rats; Reproduction