Effects of growth hormone on cytochrome P-450j.
Hypophysectomy of male and female rats resulted in a 5 and 10-fold increase respectively, in cytochrome P-450j as determined by immunoblotting. Treatment of hypophysectomized rats with growth hormone resulted in a decrease in P-450j. Microsomal N-nitrosodimethylamine demethylase activity was increased approximately 23 and 75 per cent in male and female rats respectively, over the activity in microsomes of intact animals. These studies suggest that hypophysectomy results in an increase in cytochrome P-450j and that growth hormone acts as a repressive factor for constitutive P-450j.
Department of Biochemistry and Molecular Biology, University of South Florida College of Medicine, Tampa 33612.
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Williams
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Simonet
D000818:Animals; D019392:Cytochrome P-450 CYP2E1; D003577:Cytochrome P-450 Enzyme System / Q000302:isolation & purification / Q000378:metabolism*; D005260:Female; D013006:Growth Hormone / Q000008:administration & dosage / Q000502:physiology*; D007016:Hypophysectomy; D007118:Immunoassay; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D010089:Oxidoreductases, N-Demethylating / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D013006:Growth Hormone; D003577:Cytochrome P-450 Enzyme System; D019392:Cytochrome P-450 CYP2E1; D010089:Oxidoreductases, N-Demethylating