Effects of intense infrasound on activities of dehydrogenase of the organ of Corti in guinea pigs

Objective To study the effect of intense infrasound on activities of dehydrogenase and morphorlogical changes of the organ of Corti in guinea pigs. Methods Twenty guinea pigs were randomly divided into five groups: 1 control group and 4 experimental groups.The experimental animals underwent an exposure to 8 Hz infrasound at 135 dB SPL for 90 minutes and were scarified at 8 hours, 2, 5 and 21 days respectively after infrasound exposure. The gray-scale values (GSV) of succinate dehydrogenase (SDH) dyeing were measured by Adobe Photoshop software and the organ of Corti were observed under standard light microscope. Results The GSVs of outer hair cell (OHC) of the organ of Corti in 4 experimental groups, especially in 2-day group, were significantly higher than that of control group. Microscopically, restricted or sporadic OHC losses and the swelling of OHC were found from the basal to third cochlear turns. Conclusion Intense infrasound can disturb energy metabolism of the OHC and cause permanent damage of OHC in guinea pigs.