Abstract: Objective To study the effect of 16 Hz infrasound on the proliferation of the neural stem cells in rats' hippocampus.Methods72 SD rats were randomized into 16 Hz-130 dB infrasound exposure group(n=24),16 Hz-90 dB infrasound exposure group(n=24)and control group(n=24).Rats of the infrasound exposure groups were exposed to 16Hz 90dB/130dB infrasound barochamber system,2 h/d for 1 d,7 d,14 d,or 21 d.Their brains were removed and anti-nestin immunohistochemistry was used to observe the neural stem cells in rats' hippocampus.ResultsThe expression of nestin in rats' hippocampus increased after exposure for once and increased with the exposure time.It reached its peak on the 14th day,decreased on the 21st day but remained higher level.The reaction of 90 dB group was weaker than that of 130 dB group.ConclusionThe brain injuries result from 16 Hz infrasound exposure can enhance the proliferation of neural stem cells in rats' hippocampus which might participate in the repair of neural injuries.

Key words: infrasound, hippocampus, neural stem cells, nestin, proliferation