title: Hepatic and pulmonary cytosolic metabolism of epoxides effects of aging on conjugation with glutathione.
abstract: In liver cytosol from male Fischer 344 rats, glutathione S-transferase specific activities with six epoxide substrates were lower in the 24-month-old (senescent) group than in the 3-month-old (young) group. With lung cytosol from males and liver and lung cytosol from females, specific activities declined with only some of the substrates. Age-related increases in protein content in male and female rat liver occurred by 12 months of age (middle-age) and remained elevated through senescence. In addition, increases in liver weights in males similarly occurred so that total metabolic rates tended to be highest in middle-aged males and similar in young and senescent groups. Few changes similar to these were found in liver cytosol from females or lung cytosol from males or females. Thus, tissue-, sex-, and substrate-specific alterations in epoxide metabolism occurred during aging.
mesh_terms: D000375:Aging; D000818:Animals; D003600:Cytosol / Q000201:enzymology / Q000378:metabolism; D004852:Epoxy Compounds / Q000378:metabolism*; D004988:Ethers, Cyclic / Q000378:metabolism*; D005260:Female; D005978:Glutathione / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008168:Lung / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats; D011916:Rats, Inbred F344; D012737:Sex Factors; D013379:Substrate Specificity; D014018:Tissue Distribution
chemical_list: D004852:Epoxy Compounds; D004988:Ethers, Cyclic; D005982:Glutathione Transferase; D005978:Glutathione