Changes in crystallin concentration in rat aqueous and vitreous humors after selenium-induced reversible cortical cataract.

Five months after selenite injection, 58% of the rats that had developed cataract earlier underwent a reversal of the cortical opacity. The purpose of this study was to determine if lenses undergoing recovery from cortical opacity reestablish their ability to retain crystallins. By direct ELISA method, the aqueous humor (AH) of control rats was found to contain 18, 39 and 10 ng/ml alpha-, beta- and gamma-crystallin, respectively, while vitreous humor (VH) contained 43, 98 and 23 ng/ml of alpha-, beta- and gamma-crystallin, respectively. In rats with mature cataracts which did not recover by 5 months after selenite injection, there was an approximately 10-fold greater crystallin concentration in the AH and about 20 times greater crystallin concentration in the VH than in the controls. In contrast, rats undergoing recovery from cortical cataract showed almost normal concentration of crystallins in the AH. While crystallins were still elevated in the VH of the rats undergoing recovery from cortical cataract, the crystallin content was lower than in the rats which did not recover. Higher crystallin concentrations in the VH could be explained by either a greater loss through the posterior capsule, or a slower turnover of VH. Decreased crystallin loss from lenses undergoing recovery suggested that the recovered lens at least partly reestablishes its ability to retain crystallins. These data may demonstrate that the lens fiber permeability is lowered while lens repair is occurring.