• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>American Journal of Physiology >Electron microprobe analysis of ouabain-exposed ciliary epithelium: PE-NPE cell couplets form the functional units.
【24h】

Electron microprobe analysis of ouabain-exposed ciliary epithelium: PE-NPE cell couplets form the functional units.

机译：哇巴因暴露的睫状上皮的电子微探针分析：PE-NPE细胞对形成功能单元。

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

Aqueous humor is secreted by the bilayered ciliary epithelium. Solutes and water enter the pigmented ciliary epithelial (PE) cell layer, cross gap junctions into the nonpigmented ciliary epithelial (NPE) cell layer, and are released into the aqueous humor. Electrical measurements suggest that heptanol reduces transepithelial ion movement by interrupting PE-NPE communication and that gap junctions may be a regulatory site of aqueous humor formation. Several lines of evidence also suggest that net ciliary epithelial transport is strongly region dependent. Divided rabbit iris-ciliary bodies were incubated in chambers under control and experimental conditions, quick-frozen, cryosectioned, and freeze-dried. Elemental intracellular contents of NPE and PE cells were determined by electron probe X-ray microanalysis. With or without heptanol, ouabain produced concentration- and time-dependent changes more markedly in anterior than in posterior epithelium. Without heptanol, there were considerable cell-to-cell variations in Na gain and K loss. However, contiguous NPE and PE cells displayed similar changes, even when nearby cell pairs were little changed by ouabain in aqueous, stromal, or both reservoirs. In contrast, with heptanol present, ouabain added to aqueous or both reservoirs produced much larger changes in NPE than in PE cells. The results indicate that 1) heptanol indeed interrupts PE-NPE junctions, providing an opportunity for electron microprobe analysis of the sidedness of modification of ciliary epithelial secretion; 2) Na and K undergo faster turnover in anterior than in posterior epithelium; and 3) PE-NPE gap junctions differ from PE-PE and NPE-NPE junctions in permitting ionic equilibration between adjoining ouabain-stressed cells.
机译：双层睫状上皮分泌房水。溶质和水进入有色的睫毛上皮（PE）细胞层，交叉连接进入无色素的上皮（NPE）细胞层，并释放到房水中。电学测量表明，庚醇通过中断PE-NPE通讯来减少跨上皮离子运动，并且间隙连接可能是房水形成的调节部位。几条证据还表明，睫状上皮的净运输是强烈的区域依赖性。将分开的兔虹膜睫状体在对照和实验条件下在培养箱中温育，速冻，冷冻切片和冷冻干燥。通过电子探针X射线显微分析确定NPE和PE细胞的元素胞内含量。有或没有庚醇，哇巴因在前上皮中产生的浓度和时间依赖性变化比后上皮更明显。如果没有庚醇，Na增益和K损耗的细胞间差异很大。然而，即使在含水，基质或两种储层中，哇巴因对附近的细胞对几乎没有影响，相邻的NPE和PE细胞也显示出相似的变化。相反，在存在庚醇的情况下，添加到水性或两个储层中的哇巴因在NPE中产生的变化要比PE细胞大得多。结果表明：1）庚醇确实中断了PE-NPE连接，为电子显微探针分析睫状上皮分泌修饰的侧面提供了机会; 2）钠和钾在前部的周转速度比后部上皮快; 3）PE-NPE间隙连接不同于PE-PE和NPE-NPE连接，其允许相邻的哇巴因应力细胞之间实现离子平衡。

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