Résumé
Objective To investigate the structure and function of cross-links on stereocilia of guinea pig outer hair cell (OHC). Method The ultrastructures of cross-links on stereocilia of guinea pig OHC were observed by scanning electron microscopy and tannic acid procedures. Results The side-links ran horizontally between OHC stereocilia. The stereocilia of the same and different row on each hair cell were joined by horizontally-running links. The side-links were observed in the first turn as well as the fourth turn. There were more side-links on the intact stereocilia than that on the disrupted arrangement. The side-links in the first turn and the fourth turn were more abundant than that in the second turn and the third turn. The side-links between stereocilia were spare if the stereocilia were separated. The number of side-links on stereocilia was proportional to the number of bulb-like structures on stereocilia. Conclusion The side-link is a kind of morphological structure on hair cells stereocilia of cochlea. The results suggest that cross-links play an important role in maintaining the structure and function of the hair cell stereocilia.
Résumé
Objective To investigate the effect of diagnostic ultrasound on cochlear hair cells in fetal guinea pigs. Methods Diagnostic ultrasound was used to irradiate the uteri of early pregnant guinea pigs(the first 15 days of gestion) and late pregnant guinea pigs(the 40th to 45th days of gestion) for 5 minutes daily. The number of cochlear hair cells in fetal guinea pigs was calculated using succinic dehydrogenase (SDH) staining, and computer image analysis system. The morphological change of cochlear hair cells was observed with scanning electron microscope(SEM). Results Compared with non-exposed control group, the number of total hair cells obviously decreased in the two exposed groups (P