Rasio E A, Bendayan M, Goresky C A
Department of Medicine, Hôpital Notre-Dame, Montréal, QC, Canada.
Circ Res. 1992 Feb;70(2):272-84. doi: 10.1161/01.res.70.2.272.
The changes in the permeability properties of the rete capillaries of the eel in response to temperature shifts were studied during countercurrent perfusion at constant flow and pressure. Tracers and oxygen were added to the arterial perfusate. From the ratio of end concentrations of arterial to venous capillaries divided by surface area, calculated from rete weight, a value for the ratio of permeability to flow, P/F, with dimensions in centimeters-2 was estimated. Because flow and surface area are constant, this provides an index of how permeability varies with time. A group of paracellular (albumin, sucrose, and sodium) and cellular (antipyrine, water, and oxygen) probes were used. When the temperature of the perfusate was raised abruptly from 25 degrees C to 35 degrees C, P/F values rose continuously and irreversibly from 0.042 +/- 0.009 to 0.281 +/- 0.112 cm-2 (mean +/- SEM) for 125I-albumin, from 0.082 +/- 0.006 to 1.74 +/- 0.070 cm-2 for [14C]sucrose, and from 0.32 +/- 0.06 to 2.78 +/- 0.62 cm-2 for 22Na, whereas they were not modified for [14C]antipyrine, [3H]water, and O2. Gradual increase of temperature was accompanied by a smaller rise in sucrose and sodium permeability and no change in albumin permeability; with decrease, the change was reversible.(ABSTRACT TRUNCATED AT 250 WORDS)
在恒定流量和压力下的逆流灌注过程中，研究了鳗鱼 rete 毛细血管通透性特性随温度变化的情况。向动脉灌注液中添加了示踪剂和氧气。根据动脉毛细血管与静脉毛细血管末端浓度之比除以由 rete 重量计算出的表面积，估算出通透性与流量之比（P/F）的值，其单位为厘米-2。由于流量和表面积恒定，这提供了一个通透性随时间变化的指标。使用了一组细胞旁（白蛋白、蔗糖和钠）和细胞内（安替比林、水和氧气）探针。当灌注液温度从 25℃突然升至 35℃时，125I -白蛋白的 P/F 值从 0.042±0.009 持续且不可逆地升至 0.281±0.112 cm-2，[14C]蔗糖的 P/F 值从 0.082±0.006 升至 1.74±0.070 cm-2，22Na 的 P/F 值从 0.32±0.06 升至 2.78±0.62 cm-2，而[14C]安替比林、[3H]水和 O2 的 P/F 值未发生改变。温度逐渐升高时，蔗糖和钠的通透性升高幅度较小，白蛋白通透性无变化；温度降低时，变化是可逆的。（摘要截短至 250 字）
