Remodeling of developing and mature arteries: endothelium, smooth muscle, and matrix.

In recent years, it has become increasingly clear that vascular structures readily remodel in response to hemodynamic cues associated with changes in blood flows. These remodeling processes are invoked by a wealth of developmental, physiologic, and pathologic phenomena. Current work is providing novel clues concerning flow sensing by endothelial cells, the signal transduction pathways that translate flow detection into endothelial responses, and some of the signals that are transmitted to the effector cells, the vascular smooth muscle cells in the media. However, most of these mechanisms relate to acute responses to altered flow, and we remain ignorant of how important they are in eliciting tissue remodeling. Also, there is very little information on the processes that accomplish "remodeling" beyond evidence that modulation of new tissue synthesis occurs. There is a potential for imaginative experiments to provide fundamental information on the genesis of the vascular structure-function relations, which now clearly span much of the pre- and postnatal life.