微波暴露对大鼠海马脑区热休克蛋白70表达的影响

目的 研究微波暴露对大鼠海马脑区热休克蛋白(HSP)70表达的变化,为阐明微波的生物效应与机制提供线索.方法 采用峰值功率密度为90、5 W/cm2的微波全身一次性辐照大鼠20min,采用反转录-聚合酶链反应(RT-PCR)法观察微波辐照后不同时相点大鼠海马脑区hsp70 mRNA表达的变化;采用免疫印迹(Western-blot)法观察微波辐照后HSP70蛋白水平的变化.结果 90、5W/cm2微波辐照后,大鼠的肛温[分别为(40.40±0.19)、(38.22±0.68)℃]以及比吸收率(SAR)值[分别为(15.09±0.81)、(5.56±0.31)W/kg]明显升高.2个微波暴露组在20 min暴露后均可见hsp70 mRNA和蛋白水平表达上调.结论 微波辐照有明显的热效应,是hsp70合成极为敏感的诱因,并可能启动了脑的内源性保护机制.

Effects of occupational microwave irradiation on heat shock protein 70 expressions in rat hippocampns

Objective To study the change of heat shock protein(HSP)70 expression after exposure to occupational microwave in rats hippocampus, and explore the role of HSP70 in the mechanism of bio-effect of microwave irradiation. Methods The animal model was established by whole body exposures in 90, 5 W/cm2 microwave irradiation field for 20 min in rats. Changes of the mRNA of hsp70 expressions in rat hippocampus at different time were studied by RT-PCR, and the protein change by Western blot. Results The mRNA and protein expression of hsp70 in rat hippocampus increased after 90 W/cm2 and 5 W/cm2 microwave irradiation for 20 min. The anal temperature and the value of SAR increased significantly. These changes were positively correlated with power and irradiation time of microwave. The results indicated that microwave irradiation led to HSP70 syntheses effectively. Conclusion Microwave irradiation can obviously induce the thermal effect and activate HSP70, and initiate the endogens protective mechanism of central nervous system.