[An electrophysiological study on the effect of antioxidant drugs against retinal ischemia-reperfusion damage]

The effects of antioxidant drugs on retinal ischemia-reperfusion damage were studied by electroretinograms (ERGs) from reperfused Dutch rabbit eyes. After inducing retinal ischemia by increasing the intraocular pressure (IOP) up to 140 mmHg for 60 minutes, the reperfusion was started by lowering the IOP to the normal level. Mannitol, polyethylene glycol superoxide dismutase (PEG-SOD), or ascorbic acid was administered by drip-infusion to the rabbits immediately after (early group) or 1 hr after (delayed group) the start of reperfusion. Saline, as a control, was administered by the same method as the early group. The a- and b-waves were recorded before the ischemia and during the reperfusion. In the early group treated by each drug, the recovery rates of the b-wave amplitudes at 4 hrs after the start of reperfusion were significantly greater than those in the controls. In the delayed group, the ERG recovery rate in rabbits treated with PEG-SOD was significantly better than in the controls. These results indicated that all these drugs were effective in protecting from the retina from the ischemia-reperfusion damage, and that some antioxidant drugs might be effective even when they were administered after the start of reperfusion.