Receptor- and phorbol ester-mediated phospholipase D activation in rat parotid involves two different pathways.
Receptor- and phorbol ester-mediated phospholipase D activation in rat parotid involves two different pathways.
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大鼠腮腺中受体和佛波酯介导的磷脂酶 D 激活涉及两种不同的途径。
DOI：
10.1152/ajpcell.1994.266.3.c692
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
B. Rossignol
中科院分区：
文献类型：
--
作者：
I. Guillemain;B. Rossignol
我们研究了用[14 C]硬脂酸预标记的大鼠腮腺腺泡中磷脂酶D（PLD）的激活。在2%乙醇的存在下，毒蕈碱和α-肾上腺素能激动剂刺激形成的[14 C]磷脂酰乙醇作为一个PLD活动的结果。钙离子载体，离子霉素，和佛波酯，4 β-佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）和佛波醇12，13-二丁酸酯（PDBu），也刺激磷脂酰乙醇的积累，但1-油基-2-乙酰基-sn-甘油（OAG），一个渗透类似物的二酰基甘油没有。白屈菜红碱和星形孢菌素，两种蛋白激酶C抑制剂，未能影响任何反应。这些结果表明，蛋白激酶C不参与PLD活性的调节。观察到PMA和受体介导的激动剂对PLD调节的细胞外钙需求之间存在差异。我们的研究结果强烈表明，PLD激活腮腺腺泡涉及不同的途径：钙依赖性途径激活受体介导的激动剂和钙非依赖性途径激活佛波酯。此外，我们观察到PLD激活不会导致磷脂酸水平的任何变化。我们建议磷脂酰转移酶活性的PLD反映了代谢途径，这可能允许在腮腺的碱交换反应。
We have investigated phospholipase D (PLD) activation in rat parotid acini prelabeled with [14C]stearic acid. In the presence of 2% ethanol, muscarinic and alpha-adrenergic agonists stimulated the formation of [14C]phosphatidylethanol as a result of a PLD activity. The calcium ionophore, ionomycin, and the phorbol esters, 4 beta-phorbol 12-myristate 13-acetate (PMA) and phorbol 12,13-dibutyrate (PDBu), also stimulated phosphatidylethanol accumulation, but 1-oleyl-2-acetyl-sn-glycerol (OAG), a permeant analogue of diacylglycerol did not. Chelerythrine and staurosporine, two inhibitors of protein kinase C, failed to affect any response. These results suggest that protein kinase C was not involved in the regulation of PLD activity. A difference between PLD regulation by PMA and receptor-mediated agonists was observed with regard to the extracellular calcium requirement. Our results strongly suggest that PLD activation in parotid acini involved different pathways: a calcium-dependent pathway activated by receptor-mediated agonists and a calcium-independent pathway activated by phorbol esters. Moreover, we observed that PLD activation did not result in any change in phosphatidic acid level. We propose that the phosphatidyl transferase activity of PLD reflected a metabolic pathway which may allow a base-exchange reaction in parotid gland.