Activation of phospholipase D-2 by P2X7 agonists in rat submandibular gland acini

摘要: Exogenous ATP stimulated phospholipase D (PLD), but not sphingomyelinase in rat submandibular gland (SMG) acini. PLD activation was dependent upon extracellular Ca(2+) and did involve intracellular mobilization or phosphoinositide-specific C activation. ATP-stimulated attenuated by inhibition downregulation of protein kinase (PKC). fully blocked the cytosolic A(2) (PLA(2)) inhibitor ONO-RS-082 partially selective Ca(2+)-dependent PLA(2) inhibitor, arachidonyl trifluoromethylketone (AACOCF(3)), bromoenol lactone, an Ca(2+)-independent PLA(2). Magnesium, which decreases concentration ATP(4-), nickel, blocks nonspecific cation channels coupled to purinergic receptors, inhibited ATP. Using reverse transcription-polymerase chain reaction Northern blotting techniques, we demonstrated that isoform PLD-2. Among various analogs, only P2Z/P2X(7) receptor agonist benzoyl-benzoyl The response nonselective P2X antagonist suramin oxidized ATP, a potent antagonist. It is concluded SMG acinar cells, PLD-2 upregulated exogenous through mechanism involving influx, PLA(2), PKC. Also, data suggest involvement P2X(7) receptors stimulation