Temporal and spatial distribution of gentamicin in the peripheral vestibular system after transtympanic administration in guinea pigs

► The saccule takes up more GTTR than other vestibular end-organs. ► GTTR extended from the apical cytoplasm at lower doses to the whole cell body in the type I hair cells with increasing dose. ► Type I hair cells other than dark cells are the primary target after injection. ► Transitional cells displayed GTTR at 24 h after injection and for up to 4 weeks.