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What is Ultra structurally , endothelial cells contain and explain in detail?
ref Robbins 9/e p76 Weibel-Palade bodies (WPBs) are the storage granules of endothelial cells, the cells that form the inner lining of the blood vessels and hea. They store and release two principal molecules, von Willebrand factor and P-selectin, and thus play a dual role in hemostasis and inflammation.