HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 290/5/C1350    most recent 00487.2005v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Beckett, C. S. Articles by McHowat, J. Search for Related Content PubMed PubMed Citation Articles by Beckett, C. S. Articles by McHowat, J.

RECEPTORS AND SIGNAL TRANSDUCTION

Activation of MAPKs in thrombin-stimulated ventricular myocytes is dependent on Ca²⁺-independent PLA₂

Department of Pathology, St. Louis University School of Medicine, St. Louis, Missouri

Submitted 27 September 2005 ; accepted in final form 1 December 2005

Thrombin stimulation of isolated rabbit ventricular myocytes activates a membrane-associated, Ca²⁺-independent PLA₂ (iPLA₂) that selectively hydrolyzes plasmalogen phospholipids and results in increased production of arachidonic acid and lysoplasmenylcholine. To determine whether MAPK regulates myocardial iPLA₂ activity, we isolated ventricular myocytes from rabbit heart by collagenase digestion and pretreated them with MAPK inhibitors before stimulating them with thrombin. Pretreatment with PD-98059 to inhibit p42/44 MAPK or SB-203580 to inhibit p38 MAPK had no significant effect on thrombin-stimulated, membrane-associated iPLA₂ activity. Thrombin stimulation resulted in significant increases in both p42/44 and p38 MAPK activity after 2 min. Pretreatment with the iPLA₂-selective inhibitor bromoenol lactone completely inhibited thrombin-stimulated MAPK activity, suggesting that activation of MAPKs was dependent on iPLA₂ activation. Ventricular myocyte MAPK activity was increased by incubation of the myocytes with lysoplasmenylcholine, a metabolite produced by iPLA₂-catalyzed membrane plasmalogen phospholipid hydrolysis. Altogether, these data suggest that activation of MAPKs occurs downstream of and is dependent on iPLA₂ activation in thrombin-stimulated rabbit ventricular myocytes.

lysoplasmenylcholine; cell signaling; protease-activated receptors

This article has been cited by other articles:

				S. J. Khundmiri, M. Ameen, N. A. Delamere, and E. D. Lederer PTH-mediated regulation of Na+-K+-ATPase requires Src kinase-dependent ERK phosphorylation Am J Physiol Renal Physiol, August 1, 2008; 295(2): F426 - F437. [Abstract] [Full Text] [PDF]

				N. Gluck, O. Schwob, M. Krimsky, and S. Yedgar Activation of cytosolic phospholipase A2 and fatty acid transacylase is essential but not sufficient for thrombin-induced smooth muscle cell proliferation Am J Physiol Cell Physiol, June 1, 2008; 294(6): C1597 - C1603. [Abstract] [Full Text] [PDF]