Blood flow-induced hemodynamic changes result in mechanical stress on blood cells and vessel walls. Increased shear stress can activate platelets and other circulating cells, triggering the rapid activation of receptors, calcium channels, and related signaling mechanisms. Shear stress can also modify the folding of extracellular molecules and directly activate mechanosensitive receptors and calcium channels. The mechanical movement of the extracellular matrix and the intracellular cortical actin cytoskeleton can change the conformation of platelet receptors and gate channel pores in the plasma membrane. Mechanosensitive platelet receptors and their downstream signaling events and metabolic products can also indirectly activate calcium channels. While the molecular composite of mechanotransduction pathways has been described in mammals, shear stress-induced platelet receptors and their cross talk with calcium channels have been incompletely characterized. In this review, we discuss current knowledge about the role of mechanosensitive platelet receptors and calcium channels in shear-dependent platelet activation and arterial thrombus formation.
Keywords: blood platelets; calcium channels; cytoskeleton; mammals; thrombosis.