Figure 2. Messenger RNA expression of MMP-1, MMP-2, and MMP-13 in response to high-impact mechanical stimuli. NS101 (normal) and MH7A (RA) cells were harvested 30, 60, and 120 min after the impulsive shock with Im = 0 (control), 20, 40, and 80. GAPDH was used as control. In (B)-(D), the asterisk denotes statistically significant changes (p < 0.01) and the bar represents the standard error of mean. (A) Representative gel images for NS101 (normal) and MH7A cells. (B) MMP-1 mRNA level of NS101 and MH7A cells. (C) MMP-2 mRNA level of NS101 and MH7A cells. (D) MMP-13 mRNA level of NS101 and MH7A cells.