The vascular compartments of neovascularization: spotlight on the microcirculation

In this review, the compartments of the vasculature will be discussed with respect to their potential contribution to the build-up of a differentiated and functionally meaningful vessel system. Chronic ischemia of muscle tissue results in microvessel rarification, which represents a potential therapeutic target, given the viability of the parenchyma. In particular, a chain of microcirculatory events will be described which--after specific endothelial activation by growth factors--enhances capillary and microcirculatory vessel formation, Backward signalling is introduced as potential mechanism to induce collateral growth, recruiting pre-existent macrovessel networks for blood supply to the increased microcirculatory cross sectional area. Potential signal cascades will be discussed.