Effect of sodium fluorescein on neurite outgrowth from the retinal explant culture: an in vitro model for retinal toxicity.

Effect of sodium fluorescein was examined on neurite outgrowth from the retinal explants of chick embryos cultured with chicken gizzard extract, containing macromolecules which promote neurite outgrowth. A dose more than 0.5 mg/ml of fluorescein completely prevented the neurite outgrowth from the retinal explants. The minimum dose of toxic effect of fluorescein on the neurite outgrowth was about 0.2 mg/ml. The fluorescein also caused lysis of pre-existing neurites which had been fully extended by gizzard extract.