Observation on testicular ultrastructure of rats exposed to infrasound of 8 Hz at 130 dB

AIM: To observe the changes of testicular ultra-structures in rats exposed to infrasound of 8 Hz at 130 dB and to explore the effect of infrasound on rat testis.METHODS: Forty-eight SD rats were randomly divided into 4 experimental groups(1,7,14 and 21 d groups) and 4 corresponding control groups.Experimental groups were exposed to infrasound of 8 Hz at 130 dB for 1,7,14 and 21 d respectively (2 h/d),while control groups were not treated with infrasound in the same capsule as the experimental ones.Testicular tissues from each group were obtained 1, 7 d and 14 d after infrasonic exposure respectively for observation under a transmission electron microscope.RESULTS: With prolonged exposure time,the ultrastructural damage of testicular cells became more and more serious,with increased numbers of apoptotic cells and abnormal sperms.Seven days after infrasonic exposure,acute changes of ultra-structure of testicular cells recovered and apoptotic cells decreased.Fourteen days after infrasonic exposure,abnormal sperms in 7,14 and 21 d groups were still more than ones in corresponding control groups.CONCLUSION: (Exposure) to infrasound(8 Hz/130 dB) leads to pathological(ultra-)structural changes,apoptosis and increased abnormal sperms on rat testis,which takes on a significant dose-effect relationship.Acute changes of ultra-structures can recover at day 7 after exposure,but abnormal sperms can't decrease to the normal level in such a short period.