Methylprednisolone ameliorates retinal photic injury in rats

Since lipid peroxidation induced by oxygen free radicals is believed to play an important role in retinal photic injury and high doses of certain steroids have been demonstrated to inhibit lipid peroxidation, we evaluated the effect of high-dose methylprednisolone sodium succinate on retinal injury inflicted by green light (490 to 580 nm, 160 to 180 foot-candles [1721.6 to 1936.8 lux]) for 24 hours in 36 rats. Animals received either intraperitoneal injections of the drug (80 mg/kg twice daily) or saline as a control, twice daily for 2 days, commencing with light exposure. The retinal photic injury was assessed 6 hours, 6 days, and 14 days after light exposure by light and electron microscopy, morphometric study of outer nuclear layer thickness and count of subretinal macrophages, and spectrophotometric measurement of rhodopsin. A beneficial effect of high-dose methylprednisolone was observed in retinal photic injury.