不同声压级次声对大鼠海马细胞凋亡的影响

目的　探讨 8Hz ,90dB/13 0dB次声作用对海马细胞凋亡的影响。方法　将雄性SD大鼠 88只随机分为 11个组 ,即对照组、90dB次声作用 1d组、7d组、14d组、2 1d组及 2 8d组 ,13 0dB次声作用 1d组、7d组、14d组、2 1d组及 2 8d组 ,每组 8只。采用细胞分离技术、荧光染色和流式细胞仪观察大鼠脑海马细胞凋亡率。结果　与对照组比较 ,90dB/1d组、13 0dB/1d组、13 0dB/7d组次声作用后 ,海马细胞未显示凋亡率增高 (P >0 .0 5 ) ;90dB/7d组、90dB/14d组、90dB/2 1d组、13 0dB/14d组、13 0dB/2 1d组次声作用后 ,海马细胞凋亡率显著增高 (P <0 .0 1,P <0 .0 5 ) ,90dB/2 1d组比 90dB/14d组明显回落 (P <0 .0 1) ,但仍高于对照组 (P <0 .0 5 ) ,90dB/14d组海马细胞凋亡率达到高峰 (P <0 .0 1) ,90dB/2 8d组及 13 0dB/2 8d组与对照组相比 ,差异无显著性意义 (P >0 .0 5 )。结论　 8Hz ,90dB/13 0dB次声作用一定时间后 ,均可导致海马细胞凋亡数量显著增高 ,尤以 90dB/14d组效应最强 ;8Hz ,90dB/13 0dB次声作用对大鼠海马细胞具有损伤效应。随作用时间延长 ,海马细胞对 8Hz ,90dB/13 0dB次声作用均可产生适应性。

Effects of different sound pressure levels of infrasound on apoptosis of hippocampal cells in rat brain

Objective To study the effect of infrasound on apoptosis of hippocampal cells. Methods Eighty-eight male SD rats were randomized into eleven groups: control group, 90dB/1d,7d,14d, 21d and 28d infrasound exposure groups;130dB/1d, 7d, 14d, 21d and 28d infrasound exposure groups. Infrasonic exposure groups were put into an infrasound field with 8Hz, 90dB or 130dB, each day for 2h. Acute cell separation and flow cytometer (FCM) techniques were used for measurement of apoptosis ratio in hippocampal cells. Results Compared with the control group, no increase of apoptosis ratio was recorded in 90dB/1d, 130dB/1d and 130dB/7d infrasound exposure groups( P >0.05),but there are increases of that in 90dB/7d ( P <0.01), 90dB/14d ( P <0.01), 90dB/21d ( P <0.05), 130dB/14d ( P <0.01) and 130dB/21d ( P <0.05) infrasound exposure groups, reaching the peak level in 90dB/14d group ( P <0.01 vs all the others), restoring in 90dB/28d and 130dB/28d infrasound exposure groups ( P >0.05). Conclusion The results showed that 8Hz, 90dB/130dB infrasound definitely induced increases of apoptosis ratio in the hippocampus cells after certain time of exposure, suggesting that there are damages occurred by infrasound field with 90dB or 130dB and some adaptation of the hippocampal cells ensued after a certain period of time.