The selective activation of the cardiac sarcolemmal sodium-calcium exchanger by plasmalogenic phosphatidic acid produced by phospholipase D.
Since plasmalogens are the predominant phospholipid of cardiac sarcolemma, the activation of the sodium-calcium exchanger by either plasmenylethanolamine or plasmalogenic phosphatidic acid generated by phospholipase D was explored. Sodium-calcium exchange activity was 7-fold greater in proteoliposomes comprised of plasmenylethanolamine compared to proteoliposomes comprised of only plasmenylcholine. Phospholipase D treatment of proteoliposomes resulted in 1 mol % conversion of plasmenylcholine or phosphatidylcholine to their respective phosphatidic acid molecular species with a concomitant 8-fold or 2-fold activation of sodium-calcium exchange activity, respectfully. Thus, phospholipase D-mediated hydrolysis of plasmalogens to phosphatidic acid may be an important mechanism for the regulation of the sodium-calcium exchanger.
Hale
C C
CC
Department of Biochemistry and Molecular Biology, St. Louis University Health Sciences Center, MO 63104, USA.
Ebeling
E G
EG
Hsu
F F
FF
Ford
D A
DA
D000818:Animals; D002417:Cattle; D006352:Heart Ventricles; D008081:Liposomes; D009206:Myocardium / Q000378:metabolism*; D010712:Phosphatidic Acids / Q000378:metabolism / Q000494:pharmacology*; D010739:Phospholipase D / Q000378:metabolism*; D010955:Plasmalogens / Q000378:metabolism / Q000494:pharmacology*; D011510:Proteolipids / Q000378:metabolism; D012508:Sarcolemma / Q000378:metabolism*; D019831:Sodium-Calcium Exchanger / Q000378:metabolism*
D008081:Liposomes; D010712:Phosphatidic Acids; D010955:Plasmalogens; D011510:Proteolipids; D019831:Sodium-Calcium Exchanger; C020791:phosphatidal ethanolamines; C020485:proteoliposomes; D010739:Phospholipase D