中文摘要：

目的探讨铝暴露对大鼠大脑皮质中β-位点切割酶1（beta—site APP cleaving enzyme1，BACE1）mRNA、蛋白表达及活力的影响。方法将16只健康清洁级雄性SD大鼠按体重随机分成4组，分别为对照（生理盐水）组和低（0．27mg／kg）、中（0．54mg／kg）、高（1．08mg／kg）剂量麦芽酚铝染毒组，每组4只。采用腹腔注射方式进行染毒，染毒容量为1ml／kg，连续染毒60d。测定大鼠大脑皮质中的BACE1 mRNA、蛋白表达及活力。结果0．54、1．08mg／kg麦芽酚铝染毒组BACE1 mRNA和蛋白表达及活力均明显高于对照组，差异具有统计学意义（P〈0．05）。且随着麦芽酚铝染毒剂量的升高，大鼠皮质BACE1 mRNA和蛋白表达及活力呈上升趋势。结论铝暴露可导致大鼠大脑皮质BACE1 mRNA、蛋白表达和活力升高。

英文摘要：

Objective To explore the effects of aluminum maltolate[Al（mal）3]-exposure on the protein and mRNA expression of β-site APP cleaving enzyme 1 （BACE1） and on the BACE1 activity in cerebral cortex of rats. Methods Sixteen SD male rats were randomly divided into four subgroups as following： normal saline group, and 0.27, 0.54, 1.08 mg/kg body weight Al （mal）3-exposed groups. Every rat received corresponding reagent of 0.2 ml i p., once a day for 60 consecutive days. The protein and mRNA expression of BACE1 were detected by ELISA and real-time quantitative PCR in cortex of rats respectively. The BACE1 activity was detected by β-secretase activity assay kit. Results The expression of BACE1 protein and mRNA in 0.54, 1.08 mg/kg Al（mal）3-exposed groups up-regulated significantly compared with those in the saline group（P〈0.05）. The BACE1 activity increased gradually as Al（mal）3 dosage increased. Compared with the saline group, the activity of BACE1 in 0.54, 1.08 mg/kg Al（mal）3-exposed groups increased significantly（P〈0.05）. Conclusion Aluminum exposure can result in the increased expression and activity of BACE1 in the cortex of rats.