MMP9 and myocardial infarction: Moreover, RDN reduced the expression of MMP-2, MMP-9, TH, GAP43, and NGF, it lessened the ability of cardiomyocytes to degrade ECM proteins, and attenuated early rupture and improved cardiac function after MI; furthermore, RDN decreased the distribution of sympathetic neural in the peri-infarct zone and it improved sympathetic neural remodeling.