Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:4.2.2.7 (
heparinase
)
1,270
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In order to identify structures in human skin that bind collagenase, sections from frozen or paraffin-embedded skin were incubated with either procollagenase or activated collagenase. After washing, bound procollagenase or collagenase was detected by immunofluorescence microscopy. In normal skin, procollagenase bound only to isolated granular dermal cells that were identified as mast cells on the basis of staining with fluoresceinated avidin and pinacyanol erythrosinate. When mast cells were degranulated by exposure to the ionophore A23187, extracellular granules bound procollagenase. Of various pathologic conditions examined, the highest binding of procollagenase occurred in specimens of urticaria pigmentosa. Procollagenase bound to granular cells and to abundant granules scattered throughout the dermis. Binding could be abolished by pre-treatment of tissue sections with
heparinase
or by pre-incubation of procollagenase with soluble heparin, suggesting that heparin is the binding agent in the granules. Activated collagenase also bound to dermal mast cells but in addition bound strongly to the dermal collagen. Enzymatic activity of activated collagenase was not inhibited by heparin in concentrations up to 10 mg/ml. There is evidence that
mast cell tryptase
can contribute to procollagenase activation. This study further supports a role for mast cells in collagenolysis by demonstrating that heparin from mast cells binds procollagenase and possibly serves as a reservoir for procollagenase, which may then subsequently be activated.
...
PMID:Dermal mast cell granules bind interstitial procollagenase and collagenase. 137 47
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.
...
PMID:Reappraisal of the expression of mast cell proteases of Mongolian gerbils (Meriones unguiculatus). 974 May 13