An improved assay of mammalian collagenase activity, and its use to determine hepatic extracellular matrix susceptibility to degradation
Lindblad, W.J.; Fuller, G.C.
Clinical Chemistry 28(10): 2134-2138
1982
ISSN/ISBN: 0009-9147 PMID: 6290103 Document Number: 196079
This rapid, sensitive method of determining collagenase (EC 3.4.24.7) activity incorporates several advantages of previous methods. Soluble [14C]acetylated collagen is prepared as the enzyme substrate and collagen-cleavage products are separated from noncleaved collagen by precipitation with dioxane/methanol. The assay is more reproducible than previous methods and has a lower detection limit, 15 mU of enzyme activity. We used the method in a competitive substrate assay with isolated extracellular hepatic matrix from cirrhotic and normal rat liver. Purified collagenase was consistently bound to normal rat matrix to a greater extent than to cirrhotic matrix, suggesting that in hepatic fibrosis the extracellular matrix is not as susceptible to collagenase degradation as that in normal liver.