Fluid absorption with and without sodium in isolated perfused snake proximal tubules.
Fluid absorption with and without sodium in isolated perfused snake proximal tubules.
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离体灌注蛇近端小管中含钠和不含钠的液体吸收。
DOI：
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发表时间：
1978
影响因子：
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通讯作者：
S. Bentley
中科院分区：
文献类型：
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作者：
W. Dantzler;S. Bentley
研究了离体灌注蛇肾近端小管的净液体吸收（JV）。在灌注液中加入标准的（150mmol /l Na+）碳酸氢盐缓冲林格液，在液中加入标准林格液加葡聚糖（4g / 100ml）， JV约为0.9 nl min-1 mm-1。从浴液中去除葡聚糖可减少约20%的JV。用胆碱替代灌注液中的钠时，JV趋近于零。而用胆碱替代浴液钠和灌注液后，JV恢复到对照水平。用四甲基铵代替钠，用蔗糖或乳糖代替氯化钠，用硫酸甲酯代替氯化物，结果相同。相比之下，用锂代替灌注液中的钠或灌注液和浴液中的钠并没有降低JV。流体吸收总是等渗的。在含钠介质中用磷酸盐或Tris代替碳酸氢盐对JV没有影响，但在无钠或低氯介质中缓冲液的存在可能对JV很重要。在灌注液和浴液中使用氯化钠或蔗糖，将温度降低10摄氏度，可使JV降低约35%。结果表明，当锂取代钠或当钠、氯或两者同时在灌注液和浴液中被其他替代时，会发生等渗流体吸收。
Net fluid absorption (JV) was studied in isolated, perfused snake (Thamnophis spp.) proximal renal tubules. With standard (150 mmol/liter Na+) bicarbonate-buffered Ringer in perfusate and standard Ringer plus dextran (4 g/100 ml) in bath, JV was about 0.9 nl min-1 mm-1. Removing dextran from bath reduced JV by about 20 percent. When sodium in perfusate was replaced with choline JV approached zero. However, when sodium in bath as well as perfusate was replaced with choline, JV returned to control level. Results were the same when sodium was replaced with tetramethyl-ammonium, sodium chloride was replaced with sucrose or lactose, or chloride was replaced with methyl sulfate. In contrast, replacing sodium in perfusate or in both perfusate and bath with lithium did not reduce JV. Fluid absorption was always isosmotic. Replacing bicarbonate with phosphate or Tris in sodium-containing media had no effect on JV, but the presence of buffer in sodium-free or low-chloride media may have been important for JV. Reducing temperature 10 degrees C reduced JV by about 35 percent with either sodium chloride or sucrose in both perfusate and bath. The results indicate that isosmotic fluid absorption can occur when lithium is substituted for sodium or when some other substitution is made for sodium, chloride, or both in perfusate and bath simultaneously.