RESUMO
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.
RESUMO
The authors investigated the possibility of transplanting cultured retinal pigment epithelial (RPE) cells to impaired retina. The authors induced injury of the outer sensory retina and RPE cells with the intravenous injection of 2% sodium iodate in forty pigmented rabbits. Transplantation of RPE cells was done by internal approach with a 30 gauge blunt needle. The neural retina spontaneously reattached within 36 hours. Light microscopic autoradiography showed that some labeled cells were attached to Bruch's membrane as early as in 2 hours and still found in 4 weeks after transplantation. Regeneration of the photoreceptor outer segment and its connection with transplanted RPE cell was not found. Present study demonstrates that cultured rabbit RPE cells can be successfully transplanted to injured rabbit retina if Bruch's membrane is intact. Although the regeneration of the photoreceptor outer segment failed to be demonstrated, further studies are necessary to confirm or disprove these results.