Department of Physiology and Pharmacology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown,
Platelets are key to the physiological processes of thrombosis and hemostasis and are repositories for biologically active mediators that influence many cellular functions such as aggregation, adhesion, growth, and mitogenesis as well as matrix formation and fibrinolysis. Platelets (or thrombo-cytes) also support the vascular endothelium, maintaining the semipermeable barrier to the passage of water and protein. Recently, two platelet phospholipids, lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P), have been demonstrated to have a myriad of biological activities including cell proliferation, migration, survival, mitogene-sis, and chemotaxis as well as matrix assembly, tumor cell invasion, and angiogenesis. LPA and S1P also enhance the barrier function of the vascular endothelium. This review will focus on the interaction of platelets and the vascular endothelium in promoting endothelial barrier function and will identify possible signaling pathways and cellular targets activated by LPA and S1P.
Was this article helpful?
This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.