Oleate uptake by cardiac myocytes is carrier mediated and involves a 40-kD plasma membrane fatty acid binding protein similar to that in liver, adipose tissue, and gut.
Uptake of [3H]oleate by canine or rat cardiac myocytes is saturable, displays the countertransport phenomenon, and is inhibited by phloretin and trypsin. Cardiac myocytes contain a basic (pI approximately 9.1) 40-kD plasma membrane fatty acid binding protein (FABPPM) analogous to those recently isolated from liver, adipose tissue, and gut, unrelated to the 12-14-kD cytosolic FABP in these same tissues. An antibody to rat liver FABPPM selectively inhibits specific uptake of [3H]oleate by rat heart myocytes at 37 degrees C, but has no influence on nonspecific [3H]oleate uptake at 4 degrees C or on specific uptake of [3H]glucose. Uptake of long-chain free fatty acids by cardiac muscle cells, liver, and adipose tissue and absorption by gut epithelial cells is a facilitated process mediated by identical or closely related plasma membrane FABPs.
Sorrentino
D
D
Department of Medicine, Mount Sinai School of Medicine, New York 10029.
Stump
D
D
Potter
B J
BJ
Robinson
R B
RB
White
R
R
Kiang
C L
CL
Berk
P D
PD
D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D001692:Biological Transport; D002352:Carrier Proteins / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D004285:Dogs; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D007583:Jejunum / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D008565:Membrane Proteins / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D008970:Molecular Weight; D009206:Myocardium / Q000276:immunology / Q000378:metabolism*; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012996:Solutions
D002352:Carrier Proteins; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D009829:Oleic Acids; D012996:Solutions; D019301:Oleic Acid