Measurement and manipulation of the oxygen in the rat anterior chamber
Current Eye Research
PURPOSE. To measure the partial pressure of oxygenin the anterior chamber of the rat eye under a variety of physiological conditions. METHODS. Polarographic oxygen electrode measurements were made in methoxyflurane-anesthetizedWistar or Sprague-Dawley rats. After ketamine-xylazine or pentobarbital induction,animals were artificially ventilated with a variety of gas mixtures; gaseswere directed over the corneal surface during measurement of the partial pressureof oxygen in the middle of the pupil at the surface of the lens. RESULTS. The partial pressure of oxygen in the anterior chamber of therat eye was measured as 63 ± 9 mm Hg (mean ± S.D.). Breathing100% oxygen and delivery of 100% oxygen to the cornea additively increasedaqueous humor oxygen partial pressure to levels above 279 ± 45 mm Hgwith the greatest increase coming from inhaled 100% oxygen. Conversely, inhalationand subsequent transcorneal delivery of 10% oxygen reduced levels to 22 ±11 mm Hg. CONCLUSIONS. These results suggest that the partial pressure of oxygenin the anterior chamber is sensitive to the environment in contact with thecornea. In the rat eye, the delivery of oxygen to the anterior chamber viatranscorneal diffusion may be more significant than for larger animals.
Fitch, C. L.,
Swedenberg, S. H.,
Livesey, J. C.
Measurement and manipulation of the oxygen in the rat anterior chamber.
Current Eye Research, 20(2), 121–126.