次声对大鼠海马区钙调依赖性蛋白激酶Ⅱ及Tau蛋白表达的影响

Effects of Infrasound on Expression of Calmodulin-dependent Protein Kinase II and Tau Protein in Hippocampus of Rats

目的探讨8 Hz、130 d B次声对大鼠海马区钙调依赖性蛋白激酶Ⅱ(Ca MKⅡ)及tau蛋白表达的影响。方法 56只雄性Sprague-Dawley大鼠随机分为对照组(n=8)、1 d组(n=8)、7 d组(n=8)、14 d组(n=32)。14 d组再分为照射后1 h、6 h、24 h、48 h亚组,每亚组8只。对照组每天次声仓内无次声作用放置2 h,其余各组8 Hz、130 d B次声照射2 h。免疫组织化学、Western blotting和ELISA方法检测各组大鼠海马区磷酸化Ca MKⅡ(p T286-Ca MKⅡ)及tau蛋白表达。结果 14 d组p T286-Ca MKⅡ水平最高(F>14.912,P<0.001),tau蛋白表达最多(F>36.229,P<0.001),7 d组次之(P<0.05)。14 d组中,次声后1 h、6 h,tau蛋白表达最高,24 h有所恢复,但仍较对照组高(P<0.05)。结论 8 Hz、130 d B次声作用后,大鼠海马区Ca MKⅡ磷酸化水平和tau蛋白表达及磷酸化水平增高,可能参与次声致大鼠学习记忆功能受损。

Objective To study the effect of infrasound on expression of calmodulin-dependent protein kinase II（Ca MKII） and tau protein in hippocampus of rats. Methods Fifty-six male Sprague-Dawley rats were randomized into control group（n=8）, 1-day group（n=8）,7-day group（n=8） and 14-day group（n=32）, and the 14-day group was subgrouped as 1-hour, 6-hour, 24-hour, 48-hour subgroups, naming after the time after infrasound exposure, 8 in each subgroup. All the test groups were put in an infrasound field with 8 Hz, 130 d B for 2hours daily, while the control group was put in the infrasound instrument without infrasound exposure for 2 hours daily. The expression of p T^286-Ca MKII and tau protein in hippocampus was detected with immunohistochemisty, Western blotting and enzyme-linked immunoabsorbent assay. Results The expression of p T^286-Ca MKII was the most in 14-day group（F〉14.912, P〈0.001）, as well as the expression of tau protein（F〉36.229, P〈0.001）, and secondary in 7-day group（P〈0.05）. For 14-day group, the expression of tau protein was the most in 1-hour and 6-hour subgroups, and dropped down in 24-hour subgroup, although more than that in the control group（P〈0.05）. Conclusion Exposure of 8 Hz, 130 d B infrasound may induce phosphorylation of Ca MKII and tau protein, and the expression of tau protein in hippocampal cells in rat, which may disturb their learning and memory function.