title: The induction of a specific form of cytochrome P-450 (P-450j) by fasting.
abstract: In previous work we have demonstrated that liver microsomal N-nitrosodimethylamine demethylase (NDMAd) activity is increased in rats by fasting, and we have postulated that this is due to the induction of a specific form of cytochrome P-450. This communication provides evidence for such a hypothesis. Fasting for 24 and 48 h caused 59 and 116% increases, respectively, in NDMAd activity in male rats, and fasting for 48 h caused a 63% increase in female rats. These increases were accompanied by corresponding increases of cytochrome P-450j (P-450ac) determined by immunoblotting. Fasting for 24 and 48 h also increased the mRNA for P-450j by 153 to 250%, as determined by hybridization with a cDNA probe of this cytochrome. The results suggest that fasting affects the gene expression of P-450j.
mesh_terms: D000818:Animals; D019392:Cytochrome P-450 CYP2E1; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis* / Q000235:genetics; D003593:Cytoplasm / Q000378:metabolism; D004247:DNA / Q000235:genetics; D005215:Fasting; D005260:Female; D007527:Isoenzymes / Q000096:biosynthesis* / Q000235:genetics; D008099:Liver / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D009693:Nucleic Acid Hybridization; D010089:Oxidoreductases, N-Demethylating / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D007527:Isoenzymes; D012333:RNA, Messenger; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D019392:Cytochrome P-450 CYP2E1; D010089:Oxidoreductases, N-Demethylating