RT Journal Article
SR Electronic
T1 Induction of Drug Metabolism
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 178
OP 183
VO 6
IS 2
A1 C. J. PARLI
A1 G. J. MANNERING
YR 1970
UL http://molpharm.aspetjournals.org/content/6/2/178.abstract
AB Previous studies from this laboratory showed that the administration of 3-methylcholanthrene and 3,4-benzpyrene caused the formation of cytochrome P1-450, which differs from cytochrome P-450 in its substrate specificity, in the difference spectra it produces with ethyl isocyanide, and in its drug-binding properties. Six polycyclic hydrocarbons, previously shown to range in inductive capacities from no activity to very high activity, were administered to rats. The various degrees of induction of 3-methyl-4-methylaminoazobenzene N-demethylase that resulted were related directly to changes in ethyl isocyanide difference spectra and aniline binding difference spectra of microsomal hemoprotein, two measurements which reflect the presence of cytochrome P1-450. When a maximally stimulatory dose of a polycyclic hydrocarbon was given, it caused finite increases in microsomal 3-methyl-4-methylaminoazobenzene N-demethylase activity and cytochrome P1-450 content, whether it was a poor, intermediate, or potent inducing agent. ACKNOWLEDGMENTS The recrystallized polycyclic hydrocarbons were supplied by Dr. J. L. Leong. The authors gratefully acknowledge the able technical assistance of Mrs. Janice Shoeman and Miss Kathy Johnson.