Scavenger Receptors Localize to Caveolae

CD36 has been localized to lipid rafts in several tissues, and we and others have shown CD36 to be localized within endothelial caveolae. CD36 has a putative role in the control of hypertension, and in angiogenesis [64,65]. CD36 in striated muscle caveolae appears to be important in the uptake and accumulation of fatty acids, in both skeletal muscle and heart [66,67]. Scavenger receptor class B, Type I is an 82-kDa glycosylated plasma membrane protein that is closely related to CD36 [6872]. SR-BI is a transmembrane protein with short cytoplasmic N-terminal and C-terminal cytoplasmic domains, two transmembrane domains, and a large extracellular domain comprising the majority of the protein [69,71,72]. SR-BI is a receptor for HDLs and has broad ligand-binding specificity. In addition to HDL, SR-BI binds native low-density lipoprotein (LDL), oxidized LDL, acetylated LDL, and anionic phospholipids, but not the many polyanions that are bound by the type-A scavenger receptors [73-75]). SR-BI is a physiological receptor for HDL and also plays a role in regulating plasma cholesterol levels; however, the function of SR-BI in cells other than hepatic or steroidogenic cells is not well understood. We have recently shown that SR-BI has additional roles in endothelial cells, regulating HDL-mediated delivery of estrogen to cells [14], and regulating HDL-mediated inhibition of a cell apoptosis pathway involving eNOS [76].

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Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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