title: Retinal oxygen tension is higher in light than dark.
abstract: The oxygen tension at the inner retinal surface in rabbits was measured with intraocular polarographic electrodes. In the air breathing rabbit, the oxygen tension is 21 +/- 9 mm Hg (mean +/- 1 SD, n = 6) in 12 foot-candles white light at the cornea. The oxygen tension falls 6 +/- 2 mm Hg (mean +/- 1 SD, n = 4, p less than 0.02) in darkness. In bright white light (800 foot-candles), the retinal oxygen tension is about 6 mm Hg higher than at 12 foot-candles. The in vivo retinal oxygen consumption was calculated to be 2.4 ml O2/100 g/min in light and 2.6 ml O2/100 g/min in dark. The higher oxygen consumption is probably responsible for the lower oxygen tension of the retina in dark as compared to light. Breathing 100% oxygen elevates the preretinal oxygen tension to 190 +/- 72 mm Hg (mean +/- 1 SD, n = 4) in light.
authors.affiliation: Duke University Medical Center, Department of Ophthalmology, Durham, North Carolina 27710.
authors.forename: E
authors.initials: E
authors.lastname: Stefánsson
mesh_terms: D000818:Animals; D003624:Darkness; D008027:Light; D008954:Models, Biological; D010100:Oxygen / Q000502:physiology*; D010101:Oxygen Consumption; D011817:Rabbits; D012160:Retina / Q000502:physiology*
chemical_list: D010100:Oxygen