Journal of Neuroscience, Vol 8, 383-394, Copyright © 1988 by Society for Neuroscience
Fluorescence recordings of electrical activity in goldfish optic tectum in vitro
PB Manis and JA Freeman
Department of Cell Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232.
Optical methods for recording electrical activity in the goldfish optic
tectum were evaluated. Tectal slices, with a short section of the optic
nerve attached, were stained with a fluorescent styryl dye. Potential-
dependent fluorescence changes following optic nerve stimulation were
monitored with a photodiode. We found that large optical signals could be
obtained. Experimental manipulations of the slice bathing solution
permitted us to identify several events that contributed to the optical
response, including activity in afferent fibers, excitatory and inhibitory
postsynaptic potentials, and presumptive glial depolarizations. These
results suggest that voltage-sensitive dyes can provide a useful
alternative method for monitoring synaptic responses in the goldfish
tectum, and may prove valuable in studying changes in the functional
synaptic organization of the tectum following manipulations of the
retinotectal pathway.