Latency is the major determinant of UDP‐glucuronosyltransferase activity in isolated hepatocytes

FEBS Letters

Fulceri, Rosella²  Benedetti, Angelo²  Garzó, Tamás¹  Bánhegyi, Gábor¹  Mandl, József¹ 

[1] 1st Institute of Biochemistry, Semmelweis Medical University, Budapest, Hungary;Istituto di Patologia Generale, University of Siena, Siena, Italy

关键词: UDP-glucuronosyltransferase;    Compartmentation;    Permeabilized cell;    Alamethicin;    Saponin;    Mouse hepatocyte;    ER;    endoplasmic reticulum;    UDPGT(s);    UDP-glucuronosyltransferase(s);    UDPGA;    UDP-glucuronic acid;    UDPNAG;    UDP-N-acetylglucosamine;    dbcAMP;    dibutyryl cyclic AMP;   

DOI  :  10.1016/0014-5793(93)80983-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The glucuronidation of p-nitrophenol was measured in intact, saponin- and alamethicin-treated isolated mouse hepatocytes. In saponin-permeabilized cells the elevation of extrareticular UDP-glucuronic acid concentration enhanced the rate of glucuronidation threefold. When intracellular membranes were also permeabilized by alamethicin, a further tenfold increase in the glucuronidation of p-nitrophenol was present. Parallel measurements of the ER mannose 6-phosphatase activity revealed that saponin selectively permeabilized the plasma membrane, whereas alamethicin permeabilized both plasma membrane and ER membranes. The inhibition of p-nitrophenol glucuronidation by dbcAMP in intact hepatocytes was still present in saponin-treated cells and disappeared in alamethicin-permeabilized hepatocytes. It is suggested that the permeability of the endoplasmic reticulum membrane is a major determinant of glucuronidation not only in microsomes but in isolated hepatocytes as well.

【 授权许可】

Unknown