ABSTRACT
Introduction: The importance of understanding how microvascular networks remodel in the adult
A key requirement for tissue function is an adequate blood supply. Consequently, the microcirculation is a common denominator for multiple pathological conditions including diabetic retinopathy, myocardial ischemia, and cancer. Microvascular remodeling is a complex continuum of molecular and cellular events and is a term used to describe any type of structural adaptation associated with a vascular network. This general phenomenon is commonly studied as one of three specifi c sub-processes: vasculogenesis, arteriogenesis, and angiogenesis. Vasculogenesis is defi ned
Department of Biomedical Engineering, Tulane University, Lindy Boggs Center, Suite 500, New Orleans, LA 70118-5698. Email: wmurfee@tulane.edu
as the de novo formation of new vessels. Arteriogenesis refers to as the maturation of new vessels and angiogenesis is defi ned as the growth of new vessels from existing ones. Work over the past twenty years has focused on understanding the major genetic and molecular factors involved in these sub-processes (Carmeliet 2004, Peirce and Skalak 2003). Advancing both our understanding of how a microvascular network changes in response to its local environment and our ability to therapeutically apply this understanding requires the identifi cation of environmental cues at specifi c locations across the hierarchy of a network. Consider an intact adult network (Fig. 1) consisting of arterioles, capillaries, and venules. The structural heterogeneity between endothelial cells along different vessels types (Fig. 1) emphasizes the importance of identifying: 1) vessel specifi c environments, 2) how these environments change during remodeling; and 3) how these changes direct endothelial cell behavior. Now consider an adult microvascular network that has undergone remodeling (Fig. 2).
