A. Tawara et al., DISTRIBUTION AND CHARACTERIZATION OF PROTEOGLYCANS ASSOCIATED WITH EXFOLIATION MATERIAL, Current eye research, 15(11), 1996, pp. 1101-1111
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.