Oxygen Dependence of Retinal S-Potential-Producing Cells
K. Negishi 1 and
G. Svaetichin 1
1 Department of Neurobiology, Instituto Venezolano de Investigaciones Cientificas, Caracas, Venezuela
Changes in the membrane potential of the S-potential-producing cells (S-cells) in the isolated retina of fish (Gerridae) were correlated with changes in oxygen concentration. During brief hypoxia the changes in potential consisted of initial depolarization and subsequent hyperpolarization to near 70 millivolts. Depolarization occurred when oxygen concentration was reduced to a level of from 13 to 10 percent, and hyperpolarization occurred on reduction from 10 to 2.5 percent; there was yariation from cell to cell. The recovery of S-cell function from anoxia was fast in oxygen but slow in air. The results show that the S-cell stops functioning in seconds without oxygen; hence this kind of cellular element in the nervous system is much more sensitive to oxygen deprivation than other cells studied thus far.
