Angiogenesis plays a critical role in wound healing. In wound healing new blood vessels are generated, then later in scar-resolving stages of the repair process, these newly formed blood vessels undergo destabilization and significant regression. ELR-negative chemokines have been shown to have angiostatic properties and are produced in high concentration late in the granulation tissue and resolving stage of wound repair. The receptor for the ELR-negative chemokines, CXCR3, is expressed on endothelial cells but its function is not known. To understand the physiologic role CXCR3 plays in regulating endothelial function, we analyzed the ability of the CXCR3 ligand, IP-10, to inhibit endothelial cell tube formation. IP-10 was able to inhibit endothelial cell tube formation alone and prevent VEGF-induced tube formation on Matrigel®. Treatment of endothelial cells with IP-10 significantly inhibited endothelial motility. Thus, the ELR-negative chemokines inhibit angiogenesis by inhibiting endothelial motility. To identify the signaling pathway(s) mediated by CXCR3 that inhibit endothelial cell motility, we looked at the regulation of key processes. As CXCR3 is a receptor known to generate cAMP, as we show in these cells, we examined PKA-mediated inhibition of calpain. Treatment of endothelial cells with VEGF induced the activation of m-calpain but costimulation with IP-10 significantly decreased m-calpain activity. Using cAMP analogs, 8-Br-cAMP, a PKA activator, is able to inhibit VEGF- induced motility and Rp-8-Br-cAMP, a PKA inhibitor, is able to reverse the inhibitory effects of IP-10 on endothelial migration and calpain activation. To further demonstrate that m-calpain is important in endothelial motility we show that siRNA knockdown of m-calpain inhibited VEGF induced migration. These data indicate that activation of CXCR3 inhibits endothelial migration through the PKA-mediated inhibition of m-calpain. These findings provide new targets to modulate the resolution phase of wound repair.