Estimation of gelatinase content in rat brain: effect of focal ischemia.
Matrix metalloproteinases degrade the extracellular matrix and are involved in a variety of diseases, including inflammatory diseases of the central nervous system. Here we estimated the content of gelatinase in rat brain under control conditions and 4 h after transient focal ischemia using gelatinolytic extraction and zymographic analysis. We also examined the expression of the MMP-9 and MMP-2 proteins by Western blot. Using the zymographic apparent gelatinase activity we estimated that brain gelatinase content was 0.44 ng/mg of protein. Ischemia induced a 1.7-fold increase at 4 h, thus showing an early MMP response to the ischemic injury. The main increase was seen for the MMP-9 proform, which was accompanied by enhanced MMP-9 protein expression. We suggest that basal cerebral MMP-9 and MMP-2 activities are involved in the maintenance of the extracellular matrix and prevent substrate accumulation, while enhanced postischemic MMP activity before cell death may contribute to edema formation and blood-brain barrier breakdown.
Planas
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AM
Departament de Farmacologia i Toxicologia, Institut d'Investigacions Biomèdiques de Barcelona, Barcelona, E-08036, Spain.
Solé
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S
Justicia
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C
Farré
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ER
D000818:Animals; D001921:Brain / Q000201:enzymology*; D017364:Collagenases / Q000378:metabolism; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism; D018093:Gelatinases / Q000032:analysis / Q000378:metabolism*; D002546:Ischemic Attack, Transient / Q000201:enzymology*; D007700:Kinetics; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D004792:Enzyme Precursors; D017364:Collagenases; D018093:Gelatinases; C120487:pro-matrix metalloproteinase 9; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9