Chemical Conversation: Red Blood Cells Send a Signal That Makes Platelets Less Sticky
Webb, S., Science News
Primarily known for their work hauling oxygen to tissues throughout the body, red blood cells may also play a part in regulating activities of another blood component. The cells can release a chemical that signals blood-clotting platelets to become less sticky and therefore less likely to clog a narrow vessel, chemists report.
Red blood cells change shape as they maneuver through the curves and narrows of the body's circulatory system. As they flex, the cells release small amounts of adenosine triphosphate (ATP), an energy-storing molecule, into the bloodstream. Earlier research had established that ATP can stimulate cells lining the walls of blood vessels to produce nitric oxide (NO), which causes the walls to relax, allowing blood to flow more easily.
Researchers also knew that platelets respond to ATP in the bloodstream by producing NO, which reduces their tendency to clump, using a technique that mimics the natural flow of blood cells, Dana Spence and his colleagues at Wayne State University in Detroit have now shown that platelets respond specifically to ATP released by red blood cells in a way that promotes blood flow.
"It's possible that red cells and platelets are communicating and working together," comments Randy Sprague of Saint Louis University in Missouri.
Spence and his collaborators pumped red blood cells and platelets through tubing 50 micrometers in diameter. They used a standard method to track ATP release within the tube, adding chemicals that react with ATP to produce a fluorescent signal. …