SELENOPROTEIN-P ASSOCIATES WITH ENDOTHELIAL-CELLS IN RAT-TISSUES

Selenoprotein P is an extracellular heparin-binding protein that has b een implicated in protecting the liver against oxidant injury. Its loc ation in liver, kidney, and brain was determined by conventional immun ohistochemistry and confocal microscopy using a polyclonal antiserum. Selenoprotein P is associated with endothelial cells in the liver and is more abundant in central regions than in portal regions. It is also present in kidney glomeruli associated with capillary endothelial cel ls. Staining of selenoprotein P in the brain is also confined to vascu lar endothelial cells. The heparin-binding properties of selenoprotein P could be the basis for its binding to tissue. Its localization to t he vicinity of endothelial cells is potentially relevant to its oxidan t defense function.