Figure 5From: Rat tail static compression model mimics extracellular matrix metabolic imbalances of matrix metalloproteinases, aggrecanases, and tissue inhibitors of metalloproteinases in intervertebral disc degeneration Immunohistochemical expression profile for matrix metalloproteinase (MMP) and aggrecanase cleavage products of aggrecan. (a) Representative immunohistochemical loaded disc nucleus pulposus (NP) and annulus fibrosus (AF) sections for aggrecan neoepitopes generated by MMPs and aggrecanases and negative control at 0, 7, 28, and 56 days of loading (bars: 50 μm). (b) Percentage of immunopositive cells of MMP-cleaved aggrecan neoepitope at 0, 7, 28, and 56 days in the loaded disc = NP: 12.6, 71.2, 66.3, 61.5, respectively, and AF: 12.6, 52.6, 65.6, 58.5, respectively; aggrecanase-cleaved aggrecan neoepitope = NP: 15.9, 59.9, 75.2, 12.3, respectively, and AF: 18.7, 48.3, 59.7, 18.4, respectively. *P < 0.05 when compared between loaded and unloaded conditions. †P < 0.05 when compared between different time points.Back to article page