Uptake of taurocholate by isolated gamma-glutamyltranspeptidase positive, putatively preneoplastic hepatocytes from 2-acetylaminofluorene treated rats.
Uptake of the bile acid taurocholate was determined in liver cells isolated from male Wistar rats fed a standard diet or a diet containing 2-acetylaminofluorene (2-AAF). In addition, uptake was analysed in unaltered, gamma-glutamyltranspeptidase (gamma-GTase) negative, and in putatively preneoplastic, gamma-GTase positive, hepatocytes separated from the total liver cell preparation isolated from the 2-AAF-treated animals. Total hepatocytes from the carcinogen-treated rats showed a approximately 50% decrease in the maximum rate of taurocholate transport compared to cells from untreated animals. Bile acid uptake in gamma-GTase positive and negative liver cells revealed that Vmax was decreased by 44 +/- 14% in the preneoplastic cell population. Since the Km value did not differ significantly it appears that the number of carrier molecules is reduced in the early preneoplastic hepatocytes. Our results show a partial loss of a liver-specific function in early preneoplastic gamma-GTase positive hepatocytes.
D015073:2-Acetylaminofluorene; D000818:Animals; D066298:In Vitro Techniques; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D011230:Precancerous Conditions / Q000139:chemically induced / Q000201:enzymology / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013656:Taurocholic Acid / Q000378:metabolism*; D005723:gamma-Glutamyltransferase / Q000032:analysis*
D013656:Taurocholic Acid; D015073:2-Acetylaminofluorene; D005723:gamma-Glutamyltransferase