Abstract
This study was conducted to determine the distribution of [^14^C]C60 in the pregnant rat and fetuses, and in the lactating rat and offspring. Pregnant rats were dosed on gestation day (gd) 15 and lactating rats were dosed on postnatal day (pnd) 8 via tail vein injection with a suspension of βΌ0.3βmg [^14^C]C60βkg^β1^ body weight prepared in polyvinylpyrrolidone (PVP), or with PVP alone. Tissues were collected at 24 and 48 h after dosing. The largest portion of the administered dose was detected in the liver (βΌ43%, pregnant dam; βΌ35%, lactating dam) and lung (βΌ25%, lactating dam). Radioactivity (βΌ6%) was distributed to the reproductive tract, placenta and fetuses of the pregnant dam. Lactating rats had radioactivity distributed to the milk (3140βdpmβg^β1^ tissue, 24βh; 1620βdpmβg^β1^ tissue, 48βh), and to the pups' GI tract (2.8%, 24βh; 4.4% 48βh) and liver (<1%). Blood radioactivity was significant at 24βh (14β19%) and at 48βh (7%) after dosing; largely accounted for in the plasma fraction. Less that 4% of the dose was recovered in the maternal spleen, heart, brain, urine or feces. Metabolomics analysis of urine indicated that dams exposed to [^14^C]C60 had decreased metabolites derived from the Krebs cycle and increased metabolites derived from the urea cycle or glycolysis, as well as alterations in the levels of some sulfurβcontaining amino acids and purine/pyrimidine metabolites. This study demonstrated that [^14^C]C60 crosses the placenta and is transmitted to offspring via the dam's milk and subsequently systemically absorbed. Copyright Β© 2009 John Wiley & Sons, Ltd.