[The role of thrombin in angiogenesis].

The formation of vasculature is a key step during embryogenesis. The vasculature and the intravascular blood compartment, which uses the former as a means of transportation, develop in a close spatial and temporal relationship. This review discusses the role of the blood coagulation system, particularly thrombin, as a tool to coordinate blood vessel formation. Mouse models indicate that a lack of coagulation factors results in impaired thrombin generation and consequently display a phenotype of disturbed cardiovascular development. Similar phenotypes are present in mouse models of impaired thrombin binding to its cellular receptor PAR1 or of disrupted signaling via G-proteins. Moreover, there is compelling evidence that thrombin signaling in vascular development cannot be explained by a model based only on the classical extrinsic and intrinsic coagulation pathways. As angiogenesis in adults follows the same signaling patterns as in embryos, it is of importance to learn about these pathways, hoping that they may serve as therapeutic targets in cardiovascular disease.