Effects of arsenite on hepatic mixed-function oxidase activity in rats.
1. Injection of arsenite (As3+) to control rats results in losses of total hepatic cytochrome P-450 and significant decreases of ethoxycoumarin O-deethylase (ECOD) and ethoxyresorufin O-deethylase (EROD) activities. However, As3+ appears to decrease the activity of these enzymes differentially, with EROD showing greater sensitivity than ECOD. 2. Injection of As3+ to rats treated with phenobarbital and isosafrole significantly decreases the total content of hepatic cytochrome P-450 and various mixed function oxidase (MFO) activities, with the exception of ECOD which appears to be insensitive to As3+. 3. 3-Methylcholanthrene administration apparently protects against the effects of As3+ on the cytochrome P-450 system, since total content of the cytochrome P-450 and various MFO activities were all insensitive to this treatment.
Albores
A
A
Toxicology Unit, Robens Institute, University of Surrey, Guildford, UK.
Cebrian
M E
ME
Connelly
J C
JC
Bach
P H
PH
Bridges
J W
JW
D000818:Animals; D001151:Arsenic / Q000494:pharmacology*; D018053:Arsenites; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000187:drug effects / Q000378:metabolism; D004790:Enzyme Induction; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D008748:Methylcholanthrene / Q000494:pharmacology; D006899:Mixed Function Oxygenases / Q000096:biosynthesis / Q000187:drug effects* / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012451:Safrole / Q000494:pharmacology
D018053:Arsenites; D008748:Methylcholanthrene; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; C015001:arsenite; D001151:Arsenic; D012451:Safrole; C015959:isosafrole; D010634:Phenobarbital