Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.2.2.7 (heparinase)
 1,270 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The sulfated proteoglycans in the normal human lamina cribrosa were studied by electron microscopy after cuprolinic blue dye binding. Within the cores of the laminar plates, three types of cuprolinic blue-positive proteoglycan filaments with different sizes were associated with collagen fibers. These filaments, which were partially sensitive to chondroitinase AC and chondroitinase B, were completely removed by chondroitinase ABC and were identified as chondroitin/dermatan sulfate proteoglycans. In addition, small punctate and filamentous structures that stained with cuprolinic blue were associated with the basal laminae of astrocytes and blood vessels. Enzyme chondroitinase ABC had no effect, but heparinase digested all of these basement membrane-associated structures, indicating that they represented heparan sulfate proteoglycan molecules. Keratanase did not affect any of the cuprolinic blue-positive materials. This investigation illustrates the ultrastructural distribution and morphology of proteoglycans in the human lamina cribrosa and provides baseline information for future studies regarding the roles of proteoglycan molecules in diseases such as glaucoma.
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PMID:Sulfated proteoglycans in the human lamina cribrosa. 163 36

We evaluated the effects of three specific glycosaminoglycan-degrading enzymes, chondroitinase ABC, testicular hyaluronidase, and heparinase, on the intraocular pressure (IOP) and the anterior chamber structures of bovine eyes. The anterior segment of freshly enucleated bovine eyes was perfused in a modified organ culture system. After each enzyme solution or its corresponding vehicle was introduced into the anterior chamber, the IOP was monitored for </=6 h. Compared to the control group, the chondroitinase ABC-treated group showed a significant IOP reduction after 1 h of perfusion. Testicular hyaluronidase and heparinase did not show any significant effect. Light microscopy revealed that chondroitinase ABC and testicular hyaluronidase induced detachment of the endothelial cells from trabecular beams in the uveal meshwork. Disruption of the tissues in the juxtacanalicular region and fragmentation of the endothelial cells facing the angular aqueous plexus were observed in the chondroitinase ABC- and heparinase-treated specimens. Electron microscopic study revealed detachment of trabecular meshwork cells from the beams and rupture of the inner wall of the aqueous plexus in all the enzyme-treated eyes. Cellular organelles and architectures were better preserved in chondroitinase ABC-treated eyes than those treated with hyaluronidase and heparinase. These results indicate that chondroitinase ABC has a pronounced effect on the IOP with relatively minor effect on the trabecular meshwork structures.
J Glaucoma 1993
PMID:Effects of glycosaminoglycan-degrading enzymes on bovine trabecular meshwork in organ culture. 1992 Apr 91