Hamster studies

Chrysene was mutagenic to Salmonella typhimurium in the presence of an exogenous metabolic system. It induced sister chromatid exchanges in one mouse study and chromosomal aberrations in one hamster study. Chrysene is metabolically activated to a 1,2-diol-3,4-epoxide that is mutagenic and carcinogenic in experimental animals and forms covalent adducts with DNA. ... 

The results of a hamster study indicated that after inhalation of barium chloride, 65% of the administered dose was deposited in the nasal region and was eventually absorbed into the body (Cuddihy and Ozog 1973b). Radioactive barium sulfate that is injected directly into the trachea of rats can be taken up into the epithelium membranes, and remain in these membranes for at least a few weeks (Gore and Patrick 1982 Takahashi and Patrick 1987). These studies have also shown that barium in the trachea can be cleared to the lymphatic system (Takahashi and Patrick 1987). 

DDT 2B e B2 Mouse liver, lung tumors, lymphomas rat liver tumors no tumors in three hamster studies... 

The whole-body retention of Hf was studied in marmosets and found to be very similar to that in rats and Chinese hamsters. Studies in Chinese hamsters showed that treatment with the chelating agent diethy-... 

Chronic Toxicity. The effects of repeated oral exposure to phthalates for periods ranging from a few days to 2 years have been studied in a number of animal species including rats, mice, hamsters, guinea pigs, ferrets, and dogs (37). 

Reproductive Toxicity. No data are available that impHcate either hexavalent or trivalent chromium compounds as reproductive toxins, unless exposure is by way of injection. The observed teratogenic effects of sodium dichromate(VI), chromic acid, and chromium (HI) chloride, adininistered by injection, as measured by dose-response relationships are close to the amount that would be lethal to the embryo, a common trait of many compounds (111). Reported teratogenic studies on hamsters (117,118), the mouse (119—121), and rabbits (122) have shown increased incidence of cleft palate, no effect, and testicular degeneration, respectively. Although the exposures for these experiments were provided by injections, in the final study (122) oral, inhalation, and dermal routes were also tried, and no testicular degeneration was found by these paths. 

Truhaut R, Gak JC, Graillot C. 1974. [Organochlorine insecticides Research work on their toxic action, its modalities and mechanisms. Part 1 Comparative study of the acute toxicity on the hamster and the rat.] Eur J Toxicol Environ Hyg 7 159-166. (French)... 

The cytotoxic activities of the 2, 2 -difluoro analog (775) of 737 against Chinese hamster ovary and tumor cells, in comparison with those of 1- -d-arabinofuranosylcytosine ara-C, a drug for leukemia), have been studied 775 is transported the faster through membrane into cells, more effectively phosphorylated by the deoxycytidine kinase (to the 5 -mono-phosphate) and, after conversion into the 5 -triphosphate, more highly accumulated in the cells, with longer duration time, than is ara-C, but nevertheless 775 is incorporated into the DNA to a lesser extent than is ara-C. These characteristics of 775 were discussed. 

The metabolism of NPYR is summarized in Figure 1. a-Hy-droxylation (2 or 5.position) leads to the unstable intermediates and decomposition of gives 4-hydroxybutyraldehyde [ ]. The latter, which exists predominantly as the cyclic hemiacetal 1, has been detected as a hepatic microsomal metabolite in rats, hamsters, and humans and from lung microsomes in rats (9-13). The role of 1 and as intermediates in the formation of 6 and 7 is supported by studies of the hydrolysis of 2-acetoxyNPYR and 4-(N-carbethoxy-N-nitrosamino)butanal, which both gave high yields of 7 (9,14). In microsomal incubations, can be readily quantified as its 2,4-dinitrophenylhydrazone derivative (15). The latter has also been detected in the urine of rats treated with NPYR ( ). 

These studies on NPYR are typical of the state of the art in cyclic nitrosamine metabolism ai d activation. The major metabolic pathways have been rather well characterized, but data on the relationship of these pathways to carcinogenesis are limited. This is especially true of the organospecific effects of NPYR and the other cyclic nitrosamines. For example, the main target organs for NPYR in the Syrian golden hamster are the trachea and nasal cavity rather than the liver. This is in spite... 

This then confiras the fact that NDELA penetrates the skin to act as an organ specific carcinogen as was also evident from the studies by Lijinsky jd on rats (25), from the reports by Edwards a on cosmetics in man (18) and from studies with Syrian golden hamsters in our laboratory (24). 

Mogilnicka, E.M. and Webb, M. (1981) Comparative studies on the distribution of gold, copper and zinc in the livers and kidneys of rats and hamsters after treatment with sodium gold-195-labeled-aurofhiomalate. Journal of Applied Toxicology, 1, 287—291. 

Nordenhall K, Dock L, Vahter M. 1998. Cross-fostering study of methyl mercury retention, demethylation and excretion in the neonatal hamster. Pharmacol Toxicol 82 132-136. 

Seidel A, Wiener M, Kruger E, et al. 1986. Studies on the lysosomal binding of 141Ce, 239Np, 239Pu and 241 Am in rat and Syrian hamster liver using carrier-free electrophoresis. Int J Rad Appl Instrum B13(5) 515-518. 

Siitterlin U, Thies W-G, Haffher H, et al. 1984. Comparative studies on the lysosomal association of monomeric 239Pu and 241Am in rat and Chinese hamster liver Analysis with sucrose, metrizamide, and percoll density gradients of subcellular binding as dependent on time. Radiat Res 98 293-306. 

No endocrine effects were seen in acute inhalation exposure to a triaryl phosphate mixture (Cellulube 220) for rabbits at 2,000 mg/m3 (Carpenter et al. 1959). In studies on rats, hamsters and rabbits no endocrine... 

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