Objective:To study the dynamic distribution of BaP in the corpus striatum by r-counting and light microscopic autoradiography

then to explore the neurotoxic mechanism of BaP.Methods:100 SD male rats were divided into control group(n=40)and test group(n=60)

experimental animals were given a single intravenous injection of 3.7×105 Bq/kg of 14CBaP while the same doses of Normal Saline were given to the control group.The rats were sacrificed at 1h

1 d

2 d

3 d and 7 d after the administration of radiolabelled BaP.During the experiment

some toxicological symptoms were observed and the ratios of brain-weight/body-weight were detected.Light microscopic autoradiography and r-counting were used to observe the dynamic distribution of BaP in the corpus striatum.Results:The change of toxicological symptoms are observed and the decrease ratios of brain-weight/body-weight are detected.R-counting shows that the percentage dose/g of 14CBaP in striatum is significant higher than in hippocampus and cortex at 1d and 2 d after administration.Light microscopic autoradiography shows that the silver granules in striatum reach the peak in 1d and sharp decrease in 2 d

which can be found even at 7d.Conclusion:BaP can penetrate the blood-brain barrier and distribute in corpus striatum

inducing CNS toxicity in SD rat.