BALB/c StCrlfC3Hf/Nctr, C57BL/6/, C57BL/6 X BALB/c F1 hybrid (B6CF1), and monohybrid-cross offspring from the breeding of B6CF1 mice were examined with respect to uterine, vaginal, and thymus responses to diethylstilbestrol (DES). About 400 mice of each genetic population were used. Weanling mice were fed DES at dietary concentrations of 2.5 to 1,000 ppb (microgram/kg feed) for 6 days and were killed by cervical dislocation about 20 hr after removal of the feed. C57BL/6, B6CF1, and the monohybrid-cross offspring did not differ in the uterine-weight response to DES, but the slope of the dose-response line was shallower for the BALB/c than for the other strains. Dietary DES concentrations of 250 ppb or more inhibited the uterotrophic response in all populations. Vaginal cornification occurred at lower concentrations of DES in the C57BL/6 strain than in the B6CF1 animals. BALB/c and monohybrid-cross offspring were indistinguishable from each other in their vaginal response to Des and were less sensitive to DES than the other mouse populations. The use of ethanol or corn oil as the solvent for mixing DES into the diet had no apparent effect on the uterine weight or vaginal response in any of the mice. DES depressed thymus weight in a dose-related fashion at dietary concentrations of 100 ppb and above in all genetic populations.
Comparative metabolism of hexamethylpararosaniline chloride, a poultry feed additive known as gentian violet, was examined in vitro in the presence of uninduced liver microsomes prepared from both sexes of four mouse strains, three rat strains, hamster, guinea pig, and chicken. Metabolites, isolated by solvent extraction and HPLC, were identified by comparison of reverse-phase HPLC retention times and electron impact mass spectral fragmentation patterns with those of standards prepared by unambiguous synthetic routes. The major metabolites were pentamethylpararosaniline and the isomeric N,N,N',N'and N,-N,",N"-tetramethylpararosanilines. The pattern of demethylated metabolites was found to be comparable among the species with little difference between the sexes. The extent of demethylation was least with mouse microsomes, and formation of N,N~~'-tetramethylpararosaniline by uninduced guinea pig microsomes was barely detectable.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.