[Isolation of and intracellular calcium mobilization in vestibular hair cells of the patients with acoustic neuroma].

OBJECTIVE

To further understand the biological features of the human vestibular organ.

METHODS

Vestibular hair cells were isolated from patients with acoustic neuroma during the surgery and intracellular free calcium concentration of the cells was monitored with calcium-sensitive dye Fura-2 and digital imaging microscopy.

RESULTS

Isolated vestibular hair cells were mainly of type I and could survive about 2.5 hours in vitro. Perfusion with 150 mmol/L KCl, induced a depolarization, resulting in a temporary increase of 340 nm/380 nm ratio from 0.52 to 1.16 within 1 min. In Ca2+ free environment, 150 mmol/L KCl failed to induce intracellular calcium increase. In the presence of 2.5 mumol/L ionomycin, there was an irreversible increase in 340 nm/380 nm ratio.

CONCLUSION

Human vestibular hair cell apparently possess voltage sensitive calcium channels. The method and observation aid in elucidating human vestibular biological features.