Fig. 5.
Kainate upregulates MMP-9 protein and induces its enzymatic activation. A, Representative sets of zymograms of either Triton X-100-soluble or -insoluble fractions from rat hippocampi after kainate treatment. Activities of latent (band a) and active (band b) MMP-9 are upregulated after 6 and 24 hr, respectively. The activity of MMP-2 remains unchanged (band c). B, Zymographic analysis of MMP-9 immunoprecipitated with the selective anti-MMP-9 antibody (Ab.1) from hippocampal protein extracts obtained from kainate-treated rats (from the same animals as analyzed inA). Activities of latent (band a) and active (band b) MMP-9 are upregulated after 6 and 24 hr, respectively. C, MMP-9 Western blot analysis of Triton X-100-insoluble fractions from hippocampal protein extracts after kainate treatment (from the same animals analyzed in A). Samples from Triton X-100-insoluble fractions at different time points (0, 2, 6, and 24 hr) were subjected to Western blotting with the anti-MMP-9 antibody. Latent (band a) and active (band b) forms of MMP-9 are upregulated after 6 and 24 hr, respectively.