Endothelium, the dynamic interface in cardiac lipid transport.
Vascular endothelium is the dynamic interface in transport of lipid from blood to myocytes in heart and arteries. The luminal surface of endothelium is the site of action of lipoprotein lipase on chylomicrons and VLDL and the site of uptake of fatty acids from albumin. Fatty acids and monoacylglycerols are transported from the lumen in an interfacial continuum of endothelial and myocyte membranes. Lipoprotein lipase is transferred from myocytes to the vascular lumen, and is anchored there, by proteoheparan sulfate in cell membranes. Insulin, needed for synthesis of lipoprotein lipase and esterification of fatty acids, is captured from the blood stream and delivered to myocytes by endothelial insulin receptors. Fatty acids, monoacylglycerols, lipoprotein lipase and insulin are transported along the same route, but by different mechanisms. The route involves the plasma membrane of endothelium and myocytes, the membrane lining transendothelial channels, and intercellular contacts.
Scow
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Endocrinology Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
Blanchette-Mackie
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D000818:Animals; D001158:Arteries / Q000378:metabolism; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism; D002914:Chylomicrons / Q000378:metabolism; D003331:Coronary Vessels / Q000378:metabolism*; D004699:Endocardium / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D050356:Lipid Metabolism; D008066:Lipolysis; D008071:Lipoprotein Lipase / Q000378:metabolism; D008079:Lipoproteins, VLDL / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*
D002352:Carrier Proteins; D002914:Chylomicrons; D005227:Fatty Acids; D007328:Insulin; D008079:Lipoproteins, VLDL; D008563:Membrane Lipids; D008565:Membrane Proteins; D008071:Lipoprotein Lipase