Ultrastructural observations on regenerating hair cells in the chick basilar papilla following aminoglycoside ototoxicity

摘要

Newly hatched chicks were injected with 50 mg/(kg·d) of gentamycin sulfate(GM) for 10 days. After injection, animals were killed on survival days 3, 6, 9and 12. The chick basi- lar papillae (BP) were observed by transmission electron microscopy(TEM). The results showed that regenerated hair cells were erupted to the basal membrane surface in the early phase. The cyto- plasm of these regenerated hair cells was heavily stained an contained numerous mitochondria. After several days, stereocilia appeared. When stereocilia bundles were formed and cuticular layer was in- tegrated, basal nerve terminals were found. The results suggested that regenerating hair cells were directly produced on the basal membrane surface following gentamycin induced ototoxicity and then proliferated and developed into mature normal hair cells.