Effects of hepatic inducers on testicular epoxide-metabolizing enzymes in the rat and mouse.
Testicular toxicants have become of increasing importance necessitating a better understanding of the possible role of testicular xenobiotic metabolism. The responsiveness of testicular microsomal epoxide hydrolase (mEH), cytosolic epoxide hydrolase (cEH), and cytosolic glutathione S-transferase (cGST) to hepatic inducers was studied in sexually mature male F344 rats and CD-1 mice. The hepatic inducers employed were phenobarbital (PB), beta-naphthoflavone (BNF), and butylated hydroxyanisole (BHA) which are known to induce cytochrome P-450, cytochrome P-448, and cGST, respectively. Hepatic mEH, cEH and cGST activities were assessed as positive controls. Measurable activities of all enzymes studied were present in the testes of both rats and mice. PB, BNF, and BHA produced the expected effects on mEH, cEH, and cGST in rat and mouse livers, whereas the testes were generally nonresponsive to the inducers. Induction of testicular cGST by PB occurred in mice but not rats and was the only testicular effect produced by the hepatic inducers in this study.
DiBiasio
K W
KW
Department of Environmental Toxicology, University of California, Davis 95616.
Silva
M H
MH
Hammock
B D
BD
Shull
L R
LR
D000818:Animals; D003600:Cytosol / Q000201:enzymology; D004790:Enzyme Induction / Q000187:drug effects; D004851:Epoxide Hydrolases / Q000378:metabolism; D004852:Epoxy Compounds / Q000378:metabolism*; D004988:Ethers, Cyclic / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000201:enzymology*; D008297:Male; D051379:Mice; D008862:Microsomes, Liver / Q000201:enzymology; D009929:Organ Size / Q000187:drug effects; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D013045:Species Specificity; D013737:Testis / Q000201:enzymology*
D004852:Epoxy Compounds; D004988:Ethers, Cyclic; D011506:Proteins; D005982:Glutathione Transferase; D004851:Epoxide Hydrolases