8 Hz 90 dB次声对大鼠海马细胞内钙离子及内质网钙通道蛋白RyRs表达的影响  

Effects of 8 Hz, 90 dB infrasound on intracellular Ca^(2+) concentration and expression of RyRs in hippocampus of rat brain

作　　者：刘朝晖[1] 陈景藻[2] 谭永霞[2] 邱建勇[2] 陈丹[3] 刘静[2] 

机构地区：[1]第四军医大学唐都医院康复理疗科,陕西西安710038 [2]第四军医大学西京医院康复理疗科 [3]第四军医大学基础部电子显微镜室,陕西西安710033

出　　处：《第四军医大学学报》2005年第2期185-188,共4页Journal of the Fourth Military Medical University

基　　金："十五"军队指令性课题No.(01L071)

摘　　要：目的:实验观察8Hz,90dB次声作用对大鼠海马细 胞内钙离子浓度([Ca2+]i)及内质网钙通道蛋白(Ryanodine receptors,RyRs)的影响,为进一步研究次声作用机制及为次声 卫生防护提供理论依据.方法:将SD大鼠60只随机分为5个 组,即对照组、次声作用1,7,14和21d组,每组再随机分为 Ca2+测定组和RyRs检测组.通过急性细胞分离、Ca2+荧光探针 及激光共聚焦显微镜观察大鼠脑海马细胞[Ca2+]i变化;采用 免疫组织化学方法观察其海马CA1及CA3区锥体细胞RyRs 表达状态.结果:频率8Hz,90dB次声分别作用2h/d,1d、7d 组于作用后海马细胞[Ca2+]i与对照组相比均无显著性差异 (均P>0.05),14d组海马细胞[Ca2+]i显著增高(P<0.01 vsallofothers),21d组明显回落,但较对照组仍然增高(P< 0.05);海马CA1及CA3区锥体细胞RyRs阳性表达细胞数,1, 7d组与对照组相比均无显著性差异(均P>0.05)。AIM: To investigate the effects of infrasound on the changes of intracellular free Ca 2+ concentration ([Ca 2+ ]i) and the expression of ryanodine receptors (RyRs) in hippocampus so as to probe the mechanism of infrasonic biological effects and provide reasonable ways of sanitation protection against infrasound. METHODS: Sixty SD rats were randomized into five groups: control group, infrasound exposed groups of 1, 7, 14 and 21 d group, and then every group above was subdivided randomly into two groups to detect [Ca 2+ ]i and the expression of RyRs, respectively. Groups exposed infrasound were put to a field with 8 Hz, 90 dB infrasound, 2 h/d. Acute cell separation, fluo-3/AM fluorescence technique and laser scanning confocal microscope were used for the measurement of intracellular free Ca 2+ level, and immunohistochemical method was used for the detection of RyRs expression. RESULTS: Compared with that in control group, no significant difference of [Ca 2+ ]i was found in 1 d and 7 d infrasonic exposure groups, but an increase of [Ca 2+ ]i was found in 14 d group(P<0.01) and 21 d group(P<0.05). The expression of RyRs in CA1 and CA3 pyramidal cells of hippocampus had no significant difference in 1 d and 7 d infrasonic exposure groups but significant decreases was found in 14 d group(P<0.01)and 21 d group(P<0.05)compared with that in control group. The correlation coefficient between the changes of [Ca 2+ ]i and the expression of RyRs was -0.977(P<0.01)in CA1 region and -0.858(P<0.05)in CA3 region, respectively. CONCLUSION: Infrasound at 8 Hz, 90 dB can induce[Ca 2+ ]i increases and down-regulate the expression of RyRs in CA1 and CA3 regions in hippocampus. These changes suggest that the increases of intracellular Ca 2+ and decreases of RyRs expression in hippocampus may play a crucial role in the mechanism of learning-memory disturbance.

关 键 词：次声 钙/分析 兰尼碱受体钙释放通道 海马 大鼠 

分 类 号：R136.2[医药卫生—劳动卫生]