Effects of infrasound on the proliferation of neural precursor cells in the dentate gyrus of adult rats

Objective To study the effects of infrasound on the proliferation of neural precursor cells in the hippocampal dentate gyrus of adult rats.Methods The rats were randomly and equally divided into normal control group,sham infrasound group and infrasound group (n=16).The rats of infrasound group were exposed to infrasound of 8 Hz at 130 dB for 7 consecutive days (2 h/d),and were sacrificed at 1,3,7 and 14 d after infrasonic exposure.Immunohistochemistry method for 5-bromodeoxyuridine (BrdU) was used to investigate the proliferation of neural precursor cells in the dentate gyrus.Results In 1 d group after infrasonic exposure,the number of BrdU positive cells in the dentate gyrus did not reveal a statistical difference compared with normal control group and sham infrasound group.In 3 and 7 d groups,the number of BrdU positive cells decreased significantly (P0.05),and returned to the baseline level at 14 d.Conclusion Infrasound of 8 Hz at 130 dB can inhibit the proliferation of neural precursor cells in normal adukt rat hippocampus,which might be associated with the change of microenvironment in rat brain caused by infrasound.