AIMTo investigate membrane electro-physiological features in vestibular ganglion neuronal population using a voltage-sensitive dye and optical recording technique.

METHODSDissociated and cultured mouse vestibular ganglion neurons were stained with an absorption voltage-sensitive dye, RH 155, and were imaged in 16 x 16 elements Photodiode arrays (PDA) optical recording system.

RESULTSWhen the cells were depolarized during perfusion with 150 mmol/L potassium solution, optical absorption of the dye that bound to the external surface of neuron membranes increased. The relative ratio (delta I/I) of optical absorption change was 0.23% +/- 0.08% (x +/- s, n = 28). These optical responses were wavelength dependent. Under our experimental conditions, photo toxicity and pharmacological effects of the dye were either absent or insignificant.

CONCLUSIONOur results suggest that optical recording provides a new, practical and less toxic method to simultaneously monitor changes in membrane potential from several cultured vestibular ganglion cells.