| Autor: |
Beckett, Caroline S., Pennington, Karin, McHowat, Jane |
| Předmět: |
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| Zdroj: |
American Journal of Physiology: Cell Physiology; May2006, Vol. 290 Issue 5, pC1350-C1354, 5p, 4 Graphs |
| Abstrakt: |
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 lysoplasmenyicholine. 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 mm. 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. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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