次声90 dB和130 dB致大鼠肝细胞损伤的超微结构改变

Changes of hepatocyte ultrastructure following exposure to infrasound of 90 dB and 130 dB in rats

目的 :探讨相同频率 (1 6Hz)不同声压水平 (90dB与 1 30dB)次声作用下大鼠肝细胞超微结构损伤特点及意义 .方法 :将雄性SD大鼠 6 6只 ,随机分为对照组 (6只 )、实验 1(90dB)和实验 2 (1 30dB)组 .根据次声作用时间 ,实验 1 ,2组各分为 1 ,7,1 4 ,2 1和 2 8d时间组 ,每组 6只 .在相同频率不同声压水平次声环境下每日暴露 1次 ,每次 2h ;取肝左右叶两个部位组织用戊二醛和锇酸固定 ,透射电镜下观察肝超微结构变化 .结果 :1d组 :90dB环境作用下肝超微结构无明显损伤变化 ,1 30dB环境作用下肝细胞内有脂滴出现 ;7,1 4和 2 1d组不同环境和天数次声作用后肝损伤出现脂滴逐渐增多和肝细胞部分变性坏死改变 ,发现肝细胞内的各种结构随次声作用次数增多其损伤程度逐渐加重 ;2 8d组其损伤程度均有一定程度恢复 .结论 :次声下可以对肝细胞超微结构造成不同程度损伤 ,2

AIM: To investigate the changes of hepatocyte ultrastructure following exposure to infrasound of 90 dB and 130 dB in rats. METHODS: Sixty six male SD rats of grade II were randomly divided into 3 groups: control group (6), experiment group 1 (30) and experiment group 2 (30). Experiment group 1 (30) and experiment group 2 (30) each had 5 subgroups: groups of 1, 7, 14, 21 and 28 day. The subgroups in experiment group 1 were exposed to 90 dB of infrasound for 2 hours each day while the subgroups in group 2 were exposed to 130 dB of infrasound for 2 hours each day. The separated liver tissues were fixed with glutaraldehyde and osmic acid and the changes of the hepatocyte ultrastructure were observed under the electron microscope. RESULTS: No obvious change was found in hepatocytes ultrastructure in the 1day group exposed to 90 dB, while fat drops were observed in hepatocyte in the 1 day group exposed to 130 dB. Gradual increases of fat drops and degenerative necrosis were found in hepatocytes and the damages became more and more serious along with the passage of time in all 7, 14 and 21 day groups. These damages were alleviated to some degree in 28 days. CONCLUSION: Infrasound can directly damage the hepatocyte ultrastructure to different degrees. The hepatocytes and liver tissues can, in some way, adapt themselves to the infrasound damage in 28 days.