Synergistic inhibition of lysophosphatidic acid signaling by charged and uncharged local anesthetics.
Synergistic inhibition of lysophosphatidic acid signaling by charged and uncharged local anesthetics.
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带电和不带电局部麻醉剂对溶血磷脂酸信号传导的协同抑制。
DOI：
10.1097/00000539-199905000-00029
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发表时间：
1999
影响因子：
5.7
通讯作者：
Durieux,ME
中科院分区：
文献类型：
--
作者：
Sullivan,LM;Hönemann,CW;Arledge,JA;Durieux,ME
我们研究了苯并咪唑（永久不带电）和QX 314（永久带电）抑制溶血磷脂酸（LPA）信号传导的机制。为了确定它们的作用部位，我们研究了这些药物单独和联合作用对非洲爪蟾卵母细胞中LPA诱导的Ca 2+依赖性Cl电流（ICl（Ca））的影响。暴露于苯并咪唑、QX 314（10-6-10-2 M）或两者10 min后，我们测量了对LPA（有和无蛋白激酶[PKC]激活/抑制）诱导的ICl（Ca）的影响以及对细胞内注射IP 3和GTP γ S诱导的ICl（Ca）的影响。LPA应用于卵母细胞导致I Cl（Ca）（50%有效浓度约10-8 M）。两种麻醉剂均浓度依赖性地抑制LPA信号传导（50%抑制浓度[IC 50]苯并咪唑0.9 mM，QX 314 0.66 mM）。该组合具有协同作用（IC 50苯并咪唑0.097 mM/QX 314 0.048 mM）。细胞内信号通路未受影响。这项研究表明，苯并咪唑和QX 314抑制LPA信号传导并协同作用，这最容易解释为存在两个不同的结合位点。缺乏对IP 3或GTP γ S诱导的I Cl（Ca）的抑制将受体鉴定为靶标。PKC的激活可以被排除作为一个潜在的机制。溶血磷脂酸可能在伤口愈合中发挥作用，其信号传导被局部麻醉药抑制。我们确定了膜受体作为局部麻醉剂的作用位点，并表明带电（QX 314）和不带电（苯并咪唑）局部麻醉剂协同抑制溶血磷脂酸信号传导，这可以通过不同结合位点的存在来解释。
We investigated the mechanism of benzocaine (permanently uncharged) and QX314 (permanently charged) inhibition of lysophosphatidic acid (LPA) signaling. To determine their site of action, we studied effects of these drugs, alone and in combination, on LPA-induced Ca 2+-dependent Cl currents (I Cl (Ca)) in Xenopus oocytes. After 10 min exposure to benzocaine, QX314 (10-6-10-2 M), or both, we measured effects on I Cl (Ca) induced by LPA (with and without protein kinase [PKC] activation/inhibition) and on I Cl (Ca) induced by the intracellular injection of IP 3 and GTP gamma S. LPA application to oocytes resulted in I Cl (Ca)(50% effective concentration approximately 10-8 M). Both anesthetics inhibited LPA signaling concentration-dependently (50% inhibitory concentration [IC 50] benzocaine 0.9 mM, QX314 0.66 mM). The combination acted synergistically (IC 50 benzocaine 0.097 mM/QX314 0.048 mM). Intracellular signaling pathways were not affected. This study shows that benzocaine and QX314 inhibit LPA signaling and act synergistically, which is most easily explained by the existence of two different binding sites. Lack of inhibition of IP 3 or GTP gamma S-induced I Cl (Ca) identifies the receptor as a target. Activation of PKC can be excluded as a potential mechanism. Implications: Lysophosphatidic acid may play a role in wound healing, and its signaling is inhibited by local anesthetics. We identified the membrane receptor as the local anesthetic site of action and showed that charged (QX314) and uncharged (benzocaine) local anesthetics inhibit lysophosphatidic acid signaling synergistically, which can be explained by the presence of different binding sites.