title: Placental transfer of ruthenium in rat and guinea-pig.
abstract: Ruthenium-106 in citrate solution was administered intravenously to rat at different stages of pregnancy and to guinea-pig either before conception or in late pregnancy. The results for rat showed that retention in the embryo/foetus measured at 3-5 days after administration increased from about 0.0002% of injected activity per embryo/foetus on day 12 of gestation to about 0.05% at birth. The relative concentrations of 106Ru in embryo/foetus and mother (Cf/Cm ratio) were about 0.1 in each case. Concentrations in the yolk sac on day 12 were about 1% g-1 compared with 0.01% g-1 in the foetus. Retention in the guinea-pig foetus in late gestation at 7 days after administration (days 50-57) was about 0.2% injected activity per foetus, corresponding to a Cf/Cm = 0.2. Retention in each foetoplacental unit was 2% of injected 106Ru with 50% in the yolk sac, 35% in the placenta and 10% in the foetus. For administration 4 weeks prior to conception, the level of 106Ru retained in the foetus on day 57 of gestation was two orders of magnitude lower than after short-term administration, with a Cf/Cm about 0.004.
authors: National Radiological Protection Board, Chilton, Didcot, UK.
authors: V M
authors: VM
authors: Levack
authors: H
authors: H
authors: Pottinger
authors: J D
authors: JD
authors: Harrison
mesh_terms: D000818:Animals; D005314:Embryonic and Fetal Development / Q000528:radiation effects; D005260:Female; D005333:Fetus / Q000378:metabolism / Q000528:radiation effects*; D006168:Guinea Pigs; D008431:Maternal-Fetal Exchange / Q000528:radiation effects*; D008954:Models, Biological; D010920:Placenta / Q000378:metabolism / Q000528:radiation effects; D011247:Pregnancy; D051381:Rats; D012429:Ruthenium Radioisotopes / Q000493:pharmacokinetics
chemical_list: D012429:Ruthenium Radioisotopes