[Mechanisms and strategies for targeting drugs to myocardial ischemic regions]

The ischemic heart disease has been endangering human health seriously. Although there are many kinds of anti-ischemic drugs, most of them are lacking in tissue specificity, which together with a remarkably reduced blood circulation in the ischemic zone often lead to a quite low drug distribution in the targets. Myocardial ischemia can cause a lot of pathophysiological changes, such as the enhanced permeability of the endothelial cell membrane, the up-regulated expression of various cell adhesion molecules on endothelium, the exposure of intracellular antigenic components, the decrease of pH within the ischemic zone, and so on. To date, some of these changes have been exploited with limited success to gain the passive, active and physicochemical targeting of diagnostic or therapeutic drugs to myocardial ischemic regions. However, more effective delivery strategies are still eagerly needed. Here, we reviewed and discussed the potential targeting-delivery mechanisms and strategies, used or may be used in the future, for myocardial ischemic regions.