Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.4 (chondroitinase)
 2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mast cell proteases in the tongue and jejunum of Mongolian gerbils (Meriones unguiculatus) were examined by enzyme-histochemical methods. Both trypsin-like (tryptase) and chymotrypsin-like (chymase) protease activities were demonstrated in mast cells in the tongue of fresh cryosections. When frozen sections of the tongue were post-fixed in various fixatives, those fixed in Carnoy's fluid showed strongest enzyme activities. Tryptase and chymase activities in paraffin sections of both tissues were well preserved when tissues were fixed in Carnoy's fluid at 4 degrees C for 15 min. However, enzyme activities in both tissues, especially in the tongue, were drastically reduced by longer fixation time and higher temperature. When Carnoy-fixed (4 degrees C for 15 min) paraffin sections were treated with heparinase I or chondroitinase ABC before enzyme-histochemical stainings for proteases, tryptase activities were lost entirely in the tongue and mostly in the jejunum by heparinase I digestion, and slightly in both organs by chondroitinase ABC digestion. In contrast, chymase activities at both sites were not influenced by these pretreatments. These results show that although mast cells in the tongue as well as in the jejunum of Mongolian gerbils contain both tryptase and chymase activities, their stability to fixations is variable among organs so that tissue fixation conditions are crucial for the preservation. At least some part of the stability of mast cell proteases is dependent on the proteoglycans present in mast cell granules.
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PMID:Reappraisal of the expression of mast cell proteases of Mongolian gerbils (Meriones unguiculatus). 974 May 13

The granules of mast cells contain a myriad of mediators that are stored and protected by the sulfated glycosaminoglycan (GAG) chains that decorate proteoglycans. Whereas heparin is the GAG predominantly associated with mast cells, mast cell proteoglycans are also decorated with heparan sulfate and chondroitin sulfate (CS). This study investigated a unique CS structure produced by mast cells that was detected with the antibody clone 2B6 in the absence of chondroitinase ABC digestion. Mast cells in rodent tissue sections were characterized using toluidine blue, Leder stain and the presence of mast cell tryptase. The novel CS epitope was identified in rodent tissue sections and localized to cells that were morphologically similar to cells chemically identified as mast cells. The rodent mast cell-like line RBL-2H3 was also shown to express the novel CS epitope. This epitope co-localized with multiple CS proteoglycans in both rodent tissue and RBL-2H3 cultured cells. These findings suggest that the novel CS epitope that decorates mast cell proteoglycans may play a role in the way these chains are structured in mast cells.
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PMID:Mast Cells Produce a Unique Chondroitin Sulfate Epitope. 2658 69