Differential activation of PKC-delta and -zeta by alpha(1)-adrenergic stimulation in human airway epithelial cells
Differential activation of PKC-delta and -zeta by alpha(1)-adrenergic stimulation in human airway epithelial cells
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DOI：
10.1152/ajpcell.1997.273.3.c937
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发表时间：
1997-09-01
影响因子：
5.5
通讯作者：
Ikebe, M
中科院分区：
文献类型：
--
作者：
Liedtke, CM;Cole, T;Ikebe, M
通过测定蛋白激酶C（PKC）亚型的表达及佛波酯（PMA）和α（1）肾上腺素能激动剂甲氧胺（methoxamine）对PKC亚型的激活作用，研究佛波酯和α（1）肾上腺素能对人气管上皮细胞Na Cl K共转运的刺激作用。在融合细胞培养物中表达PKC-α、-β（II）、-δ、-β和-zeta。未检测到PKC-β（1）、-γ和-eta。PKC-α和-zeta定位于胞质溶胶，和PKC-β（II）和-δ之间的胞质溶胶和颗粒组分分布大致均匀。PMA处理30分钟增加PKC活性的亚细胞组分，并诱导PKC-β（II）和-δ的颗粒部分的重新分配。PMA治疗18小时降低PKC活性的水平，发现在未经处理的细胞和减少，但没有耗尽，PKC同种型质量。甲氧胺瞬时增加PKC活性，在40秒时达到最大水平，并导致PKC-δ和-zeta质量向颗粒部分的转变。甲氧胺选择性诱导PKC-zeta活性持续增加，但PKC-δ仅短暂增加。这些结果表明，PKC-δ和-zeta介导激素激活的钠-氯-钾共转运。
Phorbol ester and alpha(1)-adrenergic stimulation of Na-Cl-K cotransport in human tracheal epithelial cells was investigated by determining the expression of protein kinase C (PKC) isotypes and their activation by phorbol 12-myristate 13-acetate (PMA) and methoxamine, an alpha(1)-adrenergic agonist. PKC-alpha, -beta(II), -delta, -epsilon, and -zeta were expressed in confluent cell cultures. PKC-beta(1), -gamma, and -eta were not detected. PKC-alpha and -zeta were localized to the cytosol, and PKC-beta(II) and -delta were distributed approximately evenly between cytosolic and particulate fractions. Treatment with PMA for 30 min increased PKC activity in subcellular fractions and induced a redistribution of PKC-beta(II) and -delta to a particulate fraction. PMA treatment for 18 h reduced PKC activity to levels found in untreated cells and reduced, but did not deplete, PKC isotype mass. Methoxamine transiently increased PKC activity, with maximal levels at 40 s, and caused a shift in PKC-delta and -zeta mass to a particulate fraction. Methoxamine selectively induced a sustained increase in PKC-zeta activity but only a transient increase in PKC-delta. These results suggest that PKC-delta and -zeta mediate hormonal activation of Na-Cl-K cotransport.