Restoration of hydroperoxide‐dependent lipid peroxidation by 3‐methylcholanthrene induction ofcytochrome P‐448 in hepatoma microsomes

FEBS Letters

Galeotti, Tommaso¹  Minotti, Giorgio¹  Palombini, Guglieimo¹  Borrello, Silvia¹ 

[1] Institute of General Pathology, Catholic University, Largo F. Vito 1, 00 168 Roma, Italy

关键词: (Morris hepatoma 9618A);    Lipid peroxidation;    Cytochrome P-448;    3-Methylcholanthrene;    Microsome t-Butyl hydroperoxide;   

DOI  :  10.1016/0014-5793(86)81132-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Microsomal membranes from the slow-growing Morris hepatoma 9618A catalyze, in the presence of t-butyl hydroperoxide, lower rates of lipid peroxidation than rat liver microsomes. The cytochrome P-450 content of hepatoma microsomes is about 40% that of the liver. SKF 525-A, an inhibitor of mixed-function oxidase, produces in hepatoma microsomes a P-450 type I binding spectrum similar to that of hepatic microsomes. The concentration of the inhibitor required for half-maximal spectral change is about 2 μM in both microsome types. SKF 525-A or ethylmorphine inhibit lipid peroxidation of normal and tumor microsomes to the same extent (about 60%). Treatment of the tumor-bearing rats with 3-methylcholanthrene increases the hepatoma cytochrome P-450 to values comparable to those of control membranes, although the hemoprotein has a peak in the CO-reduced difference absorption spectrum at 448 nm. The cytochrome P-448 induction is accompanied by an almost complete restoration of the hydroperoxide-dependent lipid peroxidation.

【 授权许可】

Unknown