Barbiturates protect retinal cells from hypoxia in cell culture
J. S. Pulido, M. Fukuda, C. A. Howe and D. G. Puro
Department of Ophthalmology, University of Iowa Hospital, Iowa City.
A culture system was used to screen for drugs that can protect mammalian
retinal cells from damage induced by hypoxia. Using a special incubator,
cultures could be made hypoxic for defined periods. Phase contrast
photomicroscopy facilitated comparison of retinal cells before hypoxia and
1 to 2 days after hypoxia. Using 2- to 3-week-old cultures, certain
glutamate antagonists, anesthetics, calcium blockers, and thiopental sodium
were screened for their effect in protecting cells from hypoxia. The most
remarkable effect was noted with thiopental. Quantitative measurements
showed a significant increase in the percent of cells surviving after
exposure to hypoxia in the presence of 100 mumol/L of thiopental sodium
compared with control hypoxic cultures--82% vs 59% at 48 hours. A
dose-response curve demonstrated maximal effect at 50 mumol/L of thiopental
sodium, with toxic effects noted at 200 mumol/L of thiopental sodium. Our
results show that thiopental reduces hypoxia-induced damage to retinal
cells in culture.
