Effects of Cumene Exposure on Synaptophysin and GFAP Expressions in Hippocampus of Rat

Lee, Kyoung-Youl;Cho, Eun-Sang;Kang, Min-Gu;Lee, Sung-Bae;Kim, Hyeon-Yeong;Son, Hwa-Young

  • Published : 20090000

Abstract

Cumene, a widely used organic solvent, decreases neuronal activity and depresses behavior in both animals and humans. However there are little known about their mechanisms on neuronal toxicity. Hippocampus, one of the limbic areas associated with learning and memory functions, is vulnerability to excitotoxicity. We investigated the effect of acute and subacute exposure of cumene on expressions of synaptophysin and glial fibrillary acidic protein (GFAP) in the hippocampi. Synaptophysin a neuronal marker of synaptogenesis, has been implicated in disorders of neurodevelopment, and GFAP a crucial role in neuronal survival is a peripheral marker of neurodegeneration. SD male rats were exposed to cumene (0, 8, 80, and 800 ppm) by inhalation chamber for 1, 14, 28, and 90 days. In Western blot analysis, the expression levels of synaptophysin in the hippocampi were significantly increased at 800 ppm on day 14 and significantly decreased at 8 ppm on day 28. Meanwhile, levels of GFAP were significantly increased in hippocampi at 1, 14 and 28 days after cumene exposure when compared to the control group. We found that cumene inhalation could effect on the expression of synaptophysin and GFAP in hippocampus, even dose of 8 ppm. These findings suggest that acute and subacute exposure of cumene may contribute to neuronal dysfunction and degeneration in rat hippocampus.

Keywords

References

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