338 formations, with exceptions, increased in proportion to the dose. The highest incidence of hydrocephalus and polydactylia was noted in the group treated with MNNG at 60 mg/kg on day 10 of pregnancy. The frequency of exencephalia was low. This study demonstrated that MNNG had a teratogenic effect, in addition to the known mutagenic and carcinogenic effects.

6 N. Inui, Y. Nishi and M. Kondo, Biological Research Center, JTS, Hatano (Japan) Transplacental in vivo/in vitro mutagenicity of AF-2, a nitrofuran, in golden hamster cells The antimicrobial food additive AF-2 was shown to have strong mutagenic effects in Escherichi coli, Neurospora crassa, silkworm and also cultured human and chinese hamster cells. Chromosomal aberrations were induced in several cultured cells and in lymphatic cells of bone marrow. However, the information a b o u t mutagenic effects of AF-2 on embryos or descendants is meager. This report deals with a mutagenic effect on embryonic hamster cells after application of AF-2 to pregnant mothers. On the l l t h day of gestation, hamsters received 20 to 200 mg per kg, of AF-2 in DMSO by intraperitoneal injection. Twenty-four hours after AF-2 treatment embryos were removed from the mother, and subcutaneous tissues of the back were cultured in Eagle's MEM supplemented with 10% fetal calf serum v/v for 48 h. Cells from mothers treated with DMSO and Hanks's solution were used for the control. Then 5 × l 0 s cells per petri dish were seeded with medium containing 8-AZ or 6-TG. The culture continued for 15 days, and the medium was changed every day for the first three days. Dishes were fixed, stained and examined. Resistant colonies appeared among cells originating from the AF-2 treated mother. The induced ratio of resistant colonies was 58.4 times in the cells from the AF-2-injected mother when selected for 10 pg 8-AZ per ml and 13.2 times in the case of selection for 5 gg of 6-TG per ml. The absolute mutant cell number in treated groups was maximal at 146 per 107 cells as compared with 2.5 in the control. AF-2, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamidel DMSO, dimethyl sulfoxidel 8-AZ, 8-azaguanine ~6 -T G, 6 -thio guanine.

Abbreviations:

7 Y. Nishi, N. Inui and M. Kondo, Biological Research Center, JTS, Hatano, (Japan) Transplacental in vivo/in vitro chemical carcinogenesis by AF-2, furylfuramide, in golden hamster cells Transplacental chemical carcinogens in vivo/in vitro has been demonstrated and developed by Di Paolo and us. In this method, chemical are metabo-

in vitro mutagenicity of AF-2, a nitrofuran, in golden hamster cells [proceedings].

338 formations, with exceptions, increased in proportion to the dose. The highest incidence of hydrocephalus and polydactylia was noted in the group t...
63KB Sizes 0 Downloads 0 Views