DISTRIBUTION AND CHARACTERIZATION OF PROTEOGLYCANS ASSOCIATED WITH EXFOLIATION MATERIAL

Purpose. To examine the distribution of proteoglycans in the exfoliati on materials in order to investigate the nature of the materials. Meth ods. The anterior parts of two eyes with exfoliation syndrome were exa mined by electron microscopy after staining with cupromeronic blue (cm b). Some specimens were treated with enzymes and/or nitrous acid prior to staining. The effects of the enzymes were evaluated statistically by counting the density of the cmb-positive filaments in the exfoliati on materials, using a computer. One eye with exfoliation syndrome stai ned with alcian blue was observed with light microscopy. Results. Exfo liation materials were observed along the epithelial cells of the iris and ciliary body, and in the trabecular meshwork and zonules. In tiss ue specimens treated with cmb, electron-dense filaments were seen asso ciated with the exfoliation materials. Microfibrils in the trabecular meshwork and iris, and zonular fibrils themselves were free of any fil ament staining, while the exfoliation materials located closely to the fibrils contained the electron-dense filaments. In the tissue specime ns treated with chondroitinase AC, chondroitinase B, chondroitinase AB C or nitrous acid before cmb staining, the amount of the filament asso ciated with exfoliation materials decreased in comparison to the contr ols. Digestion with keratinase did not demonstrate any significant cha nges in staining. A combination treatment with chondroitinase ABC and nitrous acid eliminated almost all filaments associated with the exfol iation materials. In the eye stained with alcian blue, the zonules tha t did not stain for the dye demonstrated an accumulation of exfoliatio n materials that stained strongly for alcian blue. Conclusions. Exfoli ation materials contain chondroitin sulfate, dermatan sulfate, heparan sulfate proteoglycans. Depositions of proteoglycans on the microfibri ls may be closely associated with the formation of exfoliation materia ls.