Measuring gill paracellular permeability with polyethylene glycol-4000 in freely swimming trout: proof of principle
Measuring gill paracellular permeability with polyethylene glycol-4000 in freely swimming trout: proof of principle
复制标题
使用聚乙二醇 4000 测量自由游动的鳟鱼的鳃旁细胞渗透性：原理证明
DOI：
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发表时间：
2014
影响因子：
2.8
通讯作者：
C. Wood
中科院分区：
文献类型：
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作者：
Lisa M. Robertson;C. Wood
游泳活动对鳃细胞旁渗透性的影响以前没有在鱼类中测量过。我们严格评估了氚标记的聚乙二醇（[3 H]PEG-4000）用于此目的，这种物质也是细胞外液体积，肾小球滤过率和饮水率的经典标志物。测试（8小时）休息淡水鳟鱼表明，当测量[3 H]PEG-4000清除从血浆中的流出方向，校正通过肾小球过滤大量排泄是必不可少的，需要导尿管。当测量[3 H]PEG-4000从流入方向的水中的清除率时，通过饮用校正显著摄取是必不可少的，需要末端肠道去除，而肾小球滤过损失最小。在对这些损失和吸收的替代途径进行校正后，[3 H]PEG-4000从血浆流出和从水中流入的清除率是相同的，表明鳃细胞旁渗透性没有得到纠正，并且可以在任一方向上进行测量。去除末端肠道的流入技术用于评估无导尿管的鳟鱼在1.2体长s-1下自由游泳8 h时的鳃细胞旁渗透性。鳃[3 H]PEG-4000清除率（通过从水中流入）显著增加约80%，与O2消耗率的类似测量增加雅阁。因此，在鳟鱼，鳃细胞旁的渗透性增加，在运动过程中，在雅阁传统的概念，呼吸系统的妥协。
The influence of swimming activity on gill paracellular permeability has not been measured previously in fishes. We critically assessed the use of tritium-labeled polyethylene glycol ([3H]PEG-4000) for this purpose, a substance that is also a classic marker for extracellular fluid volume, glomerular filtration rate and drinking rate. Tests (8 h) on resting freshwater trout showed that when measuring [3H]PEG-4000 clearance from the plasma in the efflux direction, correction for a large excretion via glomerular filtration was essential, necessitating urinary catheterization. When measuring [3H]PEG-4000 clearance from the water in the influx direction, correction for a significant uptake by drinking was essential, necessitating terminal gut removal, whereas glomerular filtration losses were minimal. After correction for these alternate routes of loss and uptake, [3H]PEG-4000 clearance rates by efflux from the plasma and by influx from the water were identical, showing that gill paracellular permeability is not rectified, and can be measured in either direction. The influx technique with terminal gut removal was used to assess gill paracellular permeability in trout without urinary catheters freely swimming at 1.2 body lengths s−1 for 8 h. Branchial [3H]PEG-4000 clearance rate (by influx from the water) increased significantly by ~80% in accord with a similar measured increase in O2 consumption rate. Thus in trout, gill paracellular permeability does increase during exercise, in accord with the traditional concept of the osmorespiratory compromise.