Fig. 7

Lung tissue MMP-2 activity after a single instillation of gastric fluid. a Representative zymogram of lung tissue homogenate showing the time course of changes in MMP-2 activity. No signal is seen for MMP-9. This zymogram is from a single set of animals (one animal sample per time point) and is representative of 4 separate sets. It shows a 62-kDa gelatinolytic band density (corresponding to the full-active MMP-2) at day 4 and 7 after instillation that is not present in the control sample or in the day 14 sample. The 72 kDa gelatinolytic band density corresponding to the pro-MMP2 remains stable in size and not different from the control band at the time points studied. b Densitometric analysis of four independent zymograms for MMP-2 activity. The ratio of full active MMP-2 (62-kDa) to inactive pro-MMP-2 (72 kDa) in percentage is shown. This ratio is significantly increased at days 4 and 7 and is similar to controls at day 14. Data represent the means ± SD. **: p < 0.01 with respect to controls