IMMUNOCHEMICAL DETECTION AND QUANTITATION OF MICROSOMAL CYTOCHROME-P-450 AND REDUCED NICOTINAMIDE ADENINE-DINUCLEOTIDE PHOSPHATE - CYTOCHROME-P-450 REDUCTASE IN THE RAT VENTRAL PROSTATE

  • 1 January 1983
    • journal article
    • research article
    • Vol. 43  (11) , 5131-5137
Abstract
Treatment with .beta.-naphthoflavone (BNF) induced 7-ethoxyresorufin O-deethylase and aryl hydrocarbon hydroxylase activities .apprx. 500-fold in the microsomal fraction of the rat ventral prostate but had no effect on aminopyrine N-demethylase or NADPH:cytochrome c reductase activities. Phenobarbital (PB) treatment did not alter any of these enzyme activities. Antibodies raised in rabbits were used to characterize the [cytochrome] P-450-dependent monooxygenase system in the rat ventral prostate. Anti-P-450 reductase IgG inhibited NADP:cytochrome c reductase activity in prostatic microsomes, and anti-P-450 BNF-B2 but not anti-P-450-B2 IgG inhibited the BNF-induced prostatic microsomal 7-ethoxyresorufin O-deethylase and aryl hydrocarbon hydroxylase activities. A high sensitive immunoblotting method was used to quantitate P-450 BNF-B2, P-450 PB-B2, and P-450 reductase in prostatic microsomes. Prostatic P-450 reductase with a molecular weight corresponding to that of purified liver P-450 reductase was detected at a level of 0.02 nmol/mg of microsomal protein. In the liver, the same enzyme amounts to 0.2 nmol/mg of microsomal protein. P-450 BNF-B2 was not detected in prostatic microsomes from control or PB-treated rats, whereas a protein band with a molecular weight corresponding to that of purified liver P-450 BNF-B2 was found in prostatic microsomes from BNF-treated rats at a level of 0.05 nmol P-450 per mg microsomal protein. P-450 PB-B2 was not detected in prostatic microsomes from control, PB-treated or BNF-treated animals. [These findings are discussed in relation to the etiology of prostatic cancer.].