Objective To study the effect of integrin β1 antisense oligodeoxynucleotide(ASODN)on the expression of F-actin in ECV-304 ceils exposed to infrasound,and to explore the pathway of infrasound signal transfer into the cells.Methods integrin β1 oligodeoxynucleotides were embedded in cationic liposome lipofectamine 2000 reagent and transfected into ECV-304 cells.Laser scanning confoeal microscopv was used to observe F-actin's expression when the cells were exposed to 16 Hz infrasound at 130 dB for 2 h.The cells' average fluorescence was examined using spectrofluorimetric quantification after immunofluorescent staining. Results Among the three false exposure groups,most fluorescein-labelled substances in the cells were in a diffuse state.There were few actin filaments,and they were tenuous and short, without direction.The cells' fluorescence intensities were almost the same.In a group exposed to infrasound,F-actin was thick and long with a longitudinal arrangement.Fluorescence intensities were strong.However,less F-actin expression was observed in the ceils of the ASODN group exposed to infrasound compared with the others similarly exposed.Correspondingly.F-actin expression in the ASODN group exposed to infrasound was almost the same as in the other exposed group.Conclusion F-actin expression can be increased in ECV-304 cells by infrasound exposure,but integrin β1 ASODN may partially inhibit its expression.The extraeellular matrix-integrin-cytoskeleton may be one of the transduetion pathways for infrasound signals into the cells.

Objective To observe the expression of polysialic acid-neural cell adhesion molecule (PSA-NCAM) in the rat hippocampus after infrasound exposure. Methods Ninety-six Sprague-Dawley rats were random-ized into a 16 Hz 130 dB infrasound exposure group (n =72) and a control group (n =24). Rats of the infrasound exposure group were exposed to 16 Hz 130 dB infrasound in a barochamber 2 h/d for 1, 7, 14 and 21 d. The rats' brains were removed and immunohistochemieal methods were used to detect the expression of PSA-NCAM in the hip-pocampus on the 1st, 7th, 14th, and 21st day during treatment and on the lat, 7th, and 14th day after the treatment ended. Results The expression of PSA-NCAM in the rats' hippocampuses increased after exposure for 1 d, reached its peak at the 14th day, then had decreased by the 21st day but remained at a higher level than in the controls (P≤ 0.05). Conclusion The expression of PSA-NCAM in the rat hippocampus is increased by exposure to 16 Hz 130 dB infrasound, but the levels recover somewhat after infrasound exposure ends. lnfrasound could induce neural injury and promote the migration of neural stem cells. PSA-NCAM might participate in the repair of neural injuries re-suiting from infrasound exposure.

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.

ObjectiveTo study the effects of Jiawei Buyang Huanwu Decoction on learning and memory abilities of mice exposed to 130 dB infrasound (16 Hz). Methods80 BALB/c mice were divided into blank-control group, infrasound-control group, infrasound and drug-treated group (it was divided into 3 sub-groups according to dose). Learning and memory abilities were measured 14 d later. ResultsCompared with blank-control group, learning and memory abilities decreased (P<0.05) in infrasound-control group. Compared with infrasound-control group, learning and memory abilities increased(P<0.01) in infrasound and drug-treated group. Conclusion16 Hz,130 dB infrasound could damage learning and memory abilities. Jiawei Buyang Huanwu Decoction could protect mice from learning and memory harm exposed to the infrasound.

Objective To study the effects of Jia Wei Bu Yang Huan Wu decoction on learning and memory abilities, superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities and the contents of malondialdehyde (MDA) in mice exposed to 16 Hz,130 dB infrasound. Methods Fifty BALB/c mice were divided into a control group (group C), an infrasound-control group (IC group), an infrasound and drug-treated group (ID group). Learning and memory abilities,SOD and GSH-PX activities and MDA contents were measured 14 d after corresponding treatment. Results Compared with those in group C, learning and memory abilities was significantly decreased(P0.05)in IC group. Compared with those in IC group, learning and memory abilities was increased(P

0.05),but there are increases of that in 90dB/7d ( 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.

Objective To study the effect of 8Hz infrasound on the expression of 5-HTR of hippocampus and temporal cortex in rats. Methods SD rats were exposed to 8Hz, 90dB,100dB or 130dB infrasound, respectively for 2 hours daily. Then the rats' brains were taken and given stained immunohistochemically for (5-hydroxy tryptamine receptor,5-HTR). The content of 5-HTR in hippocampus and temporal cortex were detected under an optical microscope. Results The animals in the infrasound groups had less expression of 5-HTR in hippocampus and temporal cortex, and the least were at the 35th day for 90dB group and 100dB group and the 28th day for 130dB group (P

Objective To observe the effects of infrasound on rat myocardial cells and to study its underlying mechanism. Methods One hundred Sprague-Dawley rats were divided into a normal control group and a infrasound exposure group, composed of various subgroups subject to exposure to infrasound for 2 hours daily for 1 d,7 d,14 d,21 d,and 28 d, respectively. The ultra-microstructure and apoptosis of the rat myocardial cells were observed, and SOD and MDA were measured. Results After exposure to infrasound, significant ultra-microstructural impairment and increased apoptosis of the myocardial cells were observed in the infrasound exposure group as compared to those of the normal control group,(P

Objective To investigate the effects of 8Hz infrasound on spatial learning ability of rats and its the underlying mechanism. Methods Forty male SD rats were randomly divided into a control group and an experiment group (consisting of the 8Hz, 90dB, 100dB and 130dB subgroups). The experimental subgroups were exposed to 8Hz, 90dB, 100dB or 130dB infrasound for 2 hours daily, respectively, for a total of 6 days. All of the rats were taken out of the infrasonic depot once a day and given Morris maze training. And at last the brain of the rats were harvested and treated with immunohistochemical staining for detection of ryanodine receptor (RyR). The content of RyR in hippocampi and temporal cortex were detected under an optical microscope. Results The rats in the 8Hz, 90dB, 100dB and 130dB subgroups showed prolonged latency in Morris training ( P =0.010, P =0.001 and P = 0.000 ). The hippocampi and temporal cortex of rats in 8Hz, 90dB, 100dB and 130dB subgroups showed less positive neurons of RyR ( P =0.000). There was a negative correlation between the latency period of rats finding the hidden platform and the content of RyR in hippocampus and temporal cortex. Conclusion Infrasound of 8Hz, 90dB, 100dB and 130dB could decrease the spatial learning ability of rats, and this was possibly related to the reduce of RyR in hippocampus and temporal cortex.

ObjectiveTo investigate effects of 8Hz 90dB and 8Hz 130dB infrasound on hippocampi ultrastructure of SD rats.Methods60 male SD rats were randomly divided into the control group and experimental group. Rats of experimental group were exposed to 8Hz 90dB or 8Hz 130dB infrasound 2 hours every day for 1,7,14, 21,28,35 and 42 days. As soon as the exposure finished,the right hippocampus of rat was taken and examined by electron microscopy.ResultsHippocampus ultrastructure of rats was changed after only one day exposure to infrasound and the longer exposure to infrasound, the worse ultrastructure changed. But during the latter period,damages of hippocampus ultrastructure became lighter. Different rules were observed between 90dB and 130dB groups.ConclusionInfrasound of 8Hz 90dB and 8Hz 130dB can make hippocampus ultrastructure of rats damaged mainly as denaturalizations. These changes are nonliner with time, and the hippocampus of rats has adaptability to infrasound.