次声作用对大鼠血视网膜屏障超微结构的损害

Damages of blood-retinal barrier ultrastructure after infrasound exposure

目的 观察次声作用对大鼠血视网膜屏障 (blood- retinal barrier,BRB)超微结构和通透性的影响。 方法 2 0只大鼠按暴露时间随机分为 5组 ,每组 4只。暴露于 16 Hz,130 d B的次声压力仓中 ,2 h/ d,分别暴露 0 (对照组 )、1、7、14、 2 1d后摘除眼球 ,硝酸镧灌注固定法制备电镜样品 ,超薄切片 ,电镜观察。 结果 随次声暴露时间的延长 ,BRB的损害加重 ,线粒体肿胀 ,内质网扩张 ,膜盘破坏 ,视网膜色素上皮 (retinalpigment epithelium,RPE)细胞变形坏死 ,核膜扩张等都随暴露时间的延长而更加明显。镧在视网膜各层都有分布 ,随着暴露时间的延长 ,镧在各层的渗漏越来越多。 结论 次声可造成一定程度的 BRB通透性损害 ;随着次声暴露时间的延长 ,损害更严重。

Objective To investigate the possible damaging effect of infrasound on ultrastructure and permeability of rats′ blood retinal barrier (BRB). Methods Twenty mature male rats, averagely divided into 5 groups according to the exposure duration, were exposed to infrasound at a 16 Hz frequency and 130 dB sound pressure level in a pressure chamber for 2 hours per day. After exposed for 0, 1 day, 7, 14, and 21 days respectively, ultrastructural changes of rats′ BRB were observed through injection of lanthanum (La) nitrate solution, which was used as a tracer to demonstrate the breakdown of the BRB. Results With prolonging the duration of infrasound exposure, BRB structure lesion, chondriosome tumefaction, endoplasmic reticulum expandedness, membrane disc damage, retinal pigment epithelial cells distortion and putrescence, karyotheca expandedness, and La leakage on each level of retina aggravated gradually. Conclusion Infrasound may cause the breakdown of BRB, and the lesions aggravated with prolonged infrasound exposure time.