Quantitative study of cochlear hair cells injuries in guinea pigs exposed to blast underpressure / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To explore the characteristics of cochlear hair cell injuries in guinea pigs exposed to blast underpressure(BUP). METHODS The guinea pigs were killed 14 days after exposure to experimental BUP. Their basilar membranes were stained by silver nitrate and the hair cell injuries were quantitatively assessed using the light microscope. RESULTS The outer hair cells(OHCs) of the guinea pigs clearly appeared to be injured following exposure to the experimental BUP at a peak underpressure varying between -22.4kPa and -63.3kPa. The most obvious injury was in the second turn and OHC loss was smallest in the first row and more severe in the second and third rows. OHC loss was seen in all of three experimental groups of animals following exposure to BUP. Furthermore, the higher the peak of underpressure, the more obvious the injury of OHCs. Quantitative morphological analysis of cochlear hair cells showed that the total OHC loss rates in all the experimental groups of guinea pigs exposed to BUP were significantly higher than that of control group animals(P