title: Mechanisms of disassembly of a mixed function oxygenase system in liver endoplasmic reticulum: II. The interrelation between lipid peroxidation and proteolytic degradation of cytochrome P-450.
abstract: The degradation of cytochrome P-450 as a result of proteolytic action of trypsin is a biphasic process. Lipid peroxidation (LPO) increases the rate of the fast phase of cytochrome P-450 degradation and its accessibility to protease. The efficiency of this process depends on the mode of LPO induction and decreases in the following order: NADPH----NADH----ascorbate-dependent LPO. The induction of the monooxygenase system increases the efficiency of proteolysis. LPO and proteolysis seem to be mutually enhancing processes which provide for a high efficiency of cytochrome P-450 degradation. LPO can be regarded as a triggering mechanism which makes various forms of cytochrome P-450 accessible to endogenous proteases.
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000201:enzymology*; D006868:Hydrolysis; D007700:Kinetics; D008054:Lipid Peroxides / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D008566:Membranes / Q000201:enzymology; D008748:Methylcholanthrene / Q000494:pharmacology; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D009249:NADP / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D014357:Trypsin
chemical_list: D008054:Lipid Peroxides; D009249:NADP; D008748:Methylcholanthrene; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D014357:Trypsin; D010634:Phenobarbital