Calcium concentration in cochlear endolymph after vestibular labyrinth injury.

The endolymphatic calcium concentration [Ca2+] is essential for acoustic transduction. This study investigated the changes in cochlear function caused by vestibular labyrinth destruction in the acute phase by measurement of the endocochlear potential and endolymphatic [Ca2+].Hartley guinea pigs underwent lateral semicircular canal transection with suctioning of the perilymph, ampullectomy, or destruction of the lateral part of the vestibule. The endocochlear potential and endolymphatic [Ca2+] showed mild change after lateral semicircular canal transection with suctioning or ampullectomy. However, the endocochlear potential decreased drastically and permanently, and the endolymphatic [Ca2+] elevated suddenly but finally normalized after vestibulotomy. Elevated endolymphatic [Ca2+] is important in the disturbance of the mechanism of cochlear function caused by vestibular labyrinth destruction.