McMillan DC, Leakey JE, Arlotto MP, McMillan JM, Hinson JA. Metabolism of the arylamide herbicide propanil. II. Effects of propanil and its derivatives on hepatic microsomal drug-metabolizing enzymes in the rat.
Toxicol Appl Pharmacol 1990;
103:102-12. [PMID:
2315923 DOI:
10.1016/0041-008x(90)90266-w]
[Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Propanil (3,4-dichloropropionanilide) is an arylamide herbicide that has been reported to be contaminated with the cytochrome P450 enzyme inducers 3,3',4,4'-tetrachloroazobenzene (TCAB) and 3,3',4,4'-tetrachloroazoxybenzene (TCAOB), which are structural analogs of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We determined if treatment of rats with TCAB, TCAOB, propanil, 3,4-dichloroaniline, TCDD, or phenobarbital induced the hepatic microsomal metabolism of propanil and 3,4-dichloroaniline. Acylamidase-catalyzed hydrolysis of propanil to 3,4-dichloroaniline was not induced by any of the pretreatments; however, hydroxylation of propanil at the 2'-position was induced by TCDD, TCAB, TCAOB, propanil, and 3,4-dichloroaniline pretreatments. Ring- and N-hydroxylations of 3,4-dichloroaniline were induced by TCDD, TCAB, TCAOB, and 3,4-dichloroaniline pretreatments. Microsomal 7-ethoxyresorufin-O-deethylase (EROD) and 7-benzoxyresorufin-O-dealkylase (BROD) activities and electrophoretic mobility of microsomal proteins suggested that cytochromes P450c and P450d were induced by TCAB and TCAOB pretreatment. EROD, BROD, and 7-pentoxyresorufin-O-dealkylase activities were slightly increased in microsomes from propanil- and 3,4-dichloroaniline-pretreated rats, which suggests that these compounds may be weak inducers of cytochrome P450 isozymes.
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