...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Experimental nephrology >Glucagon acutely inhibits but chronically activates Na(+)/H(+) antiporter 3 activity in OKP cells.
【24h】

Glucagon acutely inhibits but chronically activates Na(+)/H(+) antiporter 3 activity in OKP cells.

机译：胰高血糖素急性抑制但长期激活OKP细胞中的Na（+）/ H（+）反转运蛋白3活性。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

BACKGROUND: We previously found that the Na(+)/H(+) exchanger 3 (NHE3) is localized in the apical membrane of the rat renal proximal tubule and thick ascending limb of Henle. In the present study, we examined the direct effect of glucagon on the opossum kidney P (OKP) cell Na(+)/H(+) antiporter, encoded by NHE3. METHODS: Na(+)/H(+) antiporter activity was measured as the rate of cell pH recovery from an acid load using 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein. Northern blot and Western blot analyses were performed using OKP NHE3 cDNA and anti-OKP-NHE3 antibodies. RESULTS: Glucagon (1 ng/ml) acutely (1 h) inhibited, but chronically (24 h) activated NHE3 activity in OKP cells. These effects were blocked by either KT5720 or RpcAMP [protein kinase A (PKA) inhibitors], and mimicked by 10(-4) M dibutyryl-cAMP. Both NHE3 mRNA and protein abundance increased with the 24-hour incubation in glucagon or dibutyryl-cAMP. Cycloheximide did not prevent a significant increase in NHE3 activity at 24 h. We therefore examined NHE3 protein abundance in the surface membrane by the biotinylation method. cAMP or glucagon significantly increased NHE3 protein abundance in the surface membrane when incubated with cycloheximide for 24 h. CONCLUSIONS: Glucagon acutely inhibits but chronically activates NHE3 activity in OKP cells via a PKA-dependent pathway. Both protein-synthesis-dependent and -independent mechanisms play important roles in the chronic activation of NHE3.
机译：背景：我们以前发现Na（+）/ H（+）交换子3（NHE3）定位于大鼠肾近端小管的顶膜和Henle的厚上升肢。在本研究中，我们检查了胰高血糖素对负鼠肾P（OKP）细胞Na（+）/ H（+）反转运蛋白（由NHE3编码）的直接作用。方法：使用2'，7'-双（羧乙基）-5（6）-羧基荧光素测定Na（+）/ H（+）反向转运活性，作为细胞从酸性负载中恢复pH的速率。使用OKP NHE3 cDNA和抗OKP-NHE3抗体进行Northern印迹和Western印迹分析。结果：胰高血糖素（1 ng / ml）被急性（1 h）抑制，但被长期（24 h）激活OKP细胞中的NHE3活性。这些作用被KT5720或RpcAMP [蛋白激酶A（PKA）抑制剂]阻断，并被10（-4）M二丁酰-cAMP模仿。在胰高血糖素或二丁酰-cAMP中孵育24小时后，NHE3 mRNA和蛋白质丰度均增加。环己酰亚胺在24 h不能阻止NHE3活性的显着增加。因此，我们通过生物素化方法检查了表面膜中NHE3蛋白的丰度。与环己酰亚胺孵育24小时后，cAMP或胰高血糖素可显着增加表面膜中NHE3蛋白的丰度。结论：胰高血糖素可通过PKA依赖性途径急性抑制OKP细胞中NHE3的活性，但会长期激活其活性。蛋白质合成依赖性和非依赖性机制在NHE3的慢性活化中均起重要作用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号