Activities of drug-metabolizing enzymes in isolated gamma-glutamyltranspeptidase positive preneoplastic hepatocytes from carcinogen treated rats.
Drug metabolizing enzyme activities were determined in isolated putatively preneoplastic, gamma-glutamyltranspeptidase (gamma-GT) positive hepatocytes from male Wistar rats fed 2-acetylaminofluorene (AAF). The cells were isolated by affinity binding to anti-gamma-GT antibody coated dishes, the resulting suspension contained 60-87% gamma-GT-positive cells. Cytochrome P-450 dependent metabolism of benzo[a]pyrene, aldrin and ethoxyresorufin was 43-54% lower than in the parent cell suspension, glucuronidation of 3-hydroxybenzo[a]pyrene (3-OH-BP) and hydrolysis of styrene oxide were increased 1.5- and 1.4-fold, respectively. The altered pattern of drug metabolizing enzyme activities in isolated gamma-GT-positive hepatocytes is consistent with the increase in resistance of preneoplastic liver cells to hepatotoxins.
Lebsanft
J
J
Luippold
G
G
Schwarz
L R
LR
D015073:2-Acetylaminofluorene; D000818:Animals; D001579:Benzopyrene Hydroxylase / Q000378:metabolism; D002273:Carcinogens / Q000633:toxicity*; D002469:Cell Separation; D002478:Cells, Cultured; D019363:Cytochrome P-450 CYP1A1; D004851:Epoxide Hydrolases / Q000378:metabolism; D014453:Glucuronosyltransferase / Q000378:metabolism; D008113:Liver Neoplasms / Q000139:chemically induced / Q000201:enzymology*; D008297:Male; D006899:Mixed Function Oxygenases / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism; D011230:Precancerous Conditions / Q000139:chemically induced / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
D002273:Carcinogens; D015073:2-Acetylaminofluorene; D006899:Mixed Function Oxygenases; D010088:Oxidoreductases; C019647:aldrin epoxidase; D001579:Benzopyrene Hydroxylase; D019363:Cytochrome P-450 CYP1A1; D005723:gamma-Glutamyltransferase; D014453:Glucuronosyltransferase; D004851:Epoxide Hydrolases