Pericytes are critical support cells for vasculature. They aid in sprout formation, promote the expression of junction proteins between endothelial cells, and help regulate blood flow. But to perform these roles, they must first be recruited by endothelial cells. Here, we use a microchannel device to create self-assembling vasculature and study the effect of inhibiting pericyte-endothelial cell communication. We explore the effect of pericytes on vascular morphology and track pericyte coverage with and without the inhibitory drug, Imatinib. We find that pericyte migration and vessel morphology are changed with inhibition of platelet-derived growth factor (PDGF) receptor. In this way, we show the value of this system for both drug development and basic biological studies.