Involvement of different protein kinases and phospholipases A_2 in phorbol ester (TPA)-induced arachidonic acid liberation in bovine platelets

M. Lehr ； K. Griessbach

《Mediators of Inflammation》 2000卷 (2000/12) Pp. 31-34

https://doi.org/10.1080/09629350050024357

摘要

THE effect of various phospholipase A_2 and protein kinase inhibitors on the arachidonic acid liberation in bovine platelets induced by the protein kinase activator 12-O-tetradecanoylphorbol-13-acetate (TPA) was studied. TPA stimulates arachidonic acid release mainly by activating group IV cytosolic PLA_2 (cPLA_2), since inhibitors of this enzyme markedly inhibited arachidonic acid formation. However, group VI Ca^(2+)- independent PLA_2 (iPLA_2) seems to contribute to the arachidonic acid liberation too, since the relatively specific iPLA_2 inhibitor bromoenol lactone (BEL) decreased arachidonic acid generation in part. The pronounced inhibition of the TPA-induced arachidonic acid release by the protein kinase C (PKC) inhibitor s GF 109203X and Ro 31-82220, respectively, and by the p38 MAP kin as e inhibitor SB 202190 suggests that the activation of the PLA_(2s) by TPA is mediated via PKC and p38 MAP kinase.

關鍵字

Phospholipase A_2 ； Protein kinase inhibitors ； 12-O-tetradecanoylphorbol-13-ac etate ； Bovine platelets