Decreased Fibronectin Levels in Aqueous Humor after Corneal Injury

Abstract

Fibronectin plays an important role in wound healing and cell differentiation. The present study measures fibronectin levels in aqueous humor from injured corneas. In response to transcorneal freezing treatments, a thickened scar-like matrix is deposited on the posterior surface of rabbit corneas. This posterior collagenous layer (PCL) is visible grossly and has a uniform diameter. Aqueous humor from eyes with established posterior corneal scarring has significantly less fibronectin compared with control eye aqueous humor. Tissue culture experiments show that corneal endothehal cells from control eyes and PCL-associated cells from injured eyes produce similar amounts of fibronectin. The marked decline in fibronectin levels in aqueous humor in scarred corneas supports the hypothesis that fibronectin plays a role in the pathological events which result from corneal injury.

Ocular irritation leads to the appearance of proteolytic activity in the aqueous humor

“…The results of the present study lead to the suggestion that also intraocular application of inhibitors of proteolysis, such as aprotinin might be beneficial in some conditions. Such therapy could reduce the occurrence and effects of acute OIR, counteract the decrease of fibronectin levels in AH after injury (Kenney et al 1986), and also assist in the plugging of treatment of lens capsule perforations with fibrinogen (Buschmann 1987). In the posterior segment topical application of aprotinin could support the use of fibrin as a temporary sealant to plug retinal holes (Nasaduke & Peyman 1986).…”