TY - JOUR
T1 - 20-Hydroxyeicosatetraenoic Acid (20-HETE) Metabolism in Coronary Endothelial Cells
AU - Kaduce, Terry L.
AU - Fang, Xiang
AU - Harmon, Shawn D.
AU - Oltman, Christine L.
AU - Dellsperger, Kevin C.
AU - Teesch, Lynn M.
AU - Gopal, V. Raj
AU - Falck, J. R.
AU - Campbell, William B.
AU - Weintraub, Neal L.
AU - Spector, Arthur A.
PY - 2004/1/23
Y1 - 2004/1/23
N2 - We have investigated the role of endothelial cells in the metabolism of 20-hydroxyeicosatetraenoic acid (20-HETE), a vasoactive mediator synthesized from arachidonic acid by cytochrome P450 ω-oxidases. Porcine coronary artery endothelial cells (PCEC) incorporated 20-[3H]HETE primarily into the sn-2 position of phospholipids through a coenzyme A-dependent process. The incorporation was reduced by equimolar amounts of arachidonic, eicosapentaenoic or 8,9-epoxyeicosatrienoic acids, but some uptake persisted even when a 10-fold excess of arachidonic acid was available. The retention of 20-[3H]HETE increased substantially when methyl arachidonoyl fluorophosphonate, but not bromoenol lactone, was added, suggesting that a Ca2+-dependent cytosolic phospholipase A2 released the 20-HETE contained in PCEC phospholipids. Addition of calcium ionophore A23187 produced a rapid release of 20-[3H]HETE from the PCEC, a finding that also is consistent with a Ca2+-dependent mobilization process. PCEC also converted 20-[3H]HETE to 20-carboxy-arachidonic acid (20-COOH-AA) and 18-, 16-, and 14-carbon β-oxidation products. 20-COOH-AA produced vasodilation in porcine coronary arterioles, but 20-HETE was inactive. These results suggest that the incorporation of 20-HETE and its subsequent conversion to 20-COOH-AA in the endothelium may be important in modulating coronary vascular function.
AB - We have investigated the role of endothelial cells in the metabolism of 20-hydroxyeicosatetraenoic acid (20-HETE), a vasoactive mediator synthesized from arachidonic acid by cytochrome P450 ω-oxidases. Porcine coronary artery endothelial cells (PCEC) incorporated 20-[3H]HETE primarily into the sn-2 position of phospholipids through a coenzyme A-dependent process. The incorporation was reduced by equimolar amounts of arachidonic, eicosapentaenoic or 8,9-epoxyeicosatrienoic acids, but some uptake persisted even when a 10-fold excess of arachidonic acid was available. The retention of 20-[3H]HETE increased substantially when methyl arachidonoyl fluorophosphonate, but not bromoenol lactone, was added, suggesting that a Ca2+-dependent cytosolic phospholipase A2 released the 20-HETE contained in PCEC phospholipids. Addition of calcium ionophore A23187 produced a rapid release of 20-[3H]HETE from the PCEC, a finding that also is consistent with a Ca2+-dependent mobilization process. PCEC also converted 20-[3H]HETE to 20-carboxy-arachidonic acid (20-COOH-AA) and 18-, 16-, and 14-carbon β-oxidation products. 20-COOH-AA produced vasodilation in porcine coronary arterioles, but 20-HETE was inactive. These results suggest that the incorporation of 20-HETE and its subsequent conversion to 20-COOH-AA in the endothelium may be important in modulating coronary vascular function.
UR - http://www.scopus.com/inward/record.url?scp=9144262957&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=9144262957&partnerID=8YFLogxK
U2 - 10.1074/jbc.M306849200
DO - 10.1074/jbc.M306849200
M3 - Article
C2 - 14612451
AN - SCOPUS:9144262957
SN - 0021-9258
VL - 279
SP - 2648
EP - 2656
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 4
ER -