Changes of scleral sulfated proteoglycans in three cases of nanophthalmos.
OBJECTIVE
To examine the composition of scleral sulfated proteoglycans in three nanophthalmic eyes by electron microscopic histochemistry.


METHODS
Scleral tissues from three cases of nanophthalmos were collected from the Niigata University Hospital for transmission electron microscopic examination. Sulfated proteoglycans were studied using the cuprolinic blue (CB) dye binding method in conjunction with enzymatic digestion.


RESULTS
Compared with the controls, the nanophthalmic sclerae were much thicker, and the collagen fibrils showed a less orderly arrangement. Twisting or fraying of collagen fibrils was noted in some areas, and fine fibrous materials surrounded the abnormal fibrils. CB-positive proteoglycan filaments were found around the collagen fibrils and in the fine fibrous materials in the nanophthalmic specimens. The number of proteoglycan filaments was smaller than that in the normal specimens. After enzymatic digestion, the CB-positive filaments were identified as dermatan/chondroitin sulfate proteoglycans. Although the number of dermatan sulfate filaments in nanophthalmos sclerae was similar to that in the controls, there were many fewer chondroitin sulfate filaments.


CONCLUSIONS
A loss of chondroitin sulfate proteoglycan was observed in nanophthalmic sclerae. The alteration may be related to the abnormal organization of collagen fibrils and the onset of uveal effusion.
Fukuchi
Takeo
T
Division of Ophthalmology and Visual Science, Niigata University, Niigata, Japan. tfuku@med.niigata-u.ac.jp.|Division of Ophthalmology and Visual Science, Niigata University, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan. tfuku@med.niigata-u.ac.jp.
Sawada
Hideko
H
Division of Ophthalmology and Visual Science, Niigata University, Niigata, Japan.
Seki
Masaaki
M
Division of Ophthalmology and Visual Science, Niigata University, Niigata, Japan.
Oyama
Tokuhide
T
Division of Ophthalmology and Visual Science, Niigata University, Niigata, Japan.
Cho
Hiroyuki
H
Division of Ophthalmology and Visual Science, Niigata University, Niigata, Japan.
Abe
Haruki
H
Division of Ophthalmology and Visual Science, Niigata University, Niigata, Japan.