Interglomerular heterogeneity of filtration fraction among superficial nephrons: fact or artifact.
Interglomerular heterogeneity of filtration fraction among superficial nephrons: fact or artifact.
复制标题
浅表肾单位滤过分数的肾小球间异质性：事实或伪影。
DOI：
10.1038/ki.1986.71
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发表时间：
1986
影响因子：
19.6
通讯作者：
Ichikawa,I
中科院分区：
文献类型：
--
作者：
Hughes,ML;Ichikawa,I
浅表肾单位滤过分数的肾小球间异质性。将通过微穿刺从随机选择的表面传出小动脉收集的血浆样品的蛋白质浓度（CE）的方差（S2inter-G）与从23只慕尼黑-威斯塔大鼠的相同传出小动脉收集和重新收集的样品的方差（S2intra-G）进行比较。在传出小动脉血液采集过程中，在采集移液管下游轻轻抽吸以保持油滴，以避免干扰肾小球自然血液流出。 S2inter-Gaveragged 0.067±0.014（SE），与S2intra-G平均值（0.075±0.016，P>0.50）相当，表明滤过分数值的肾小球间异质性程度太小，无法用这种微穿刺技术检测。当使用不受控制的抽吸压力收集另外 10 个样品时，S2inter-Gaverages 为 1.15 ± 1.30，该值明显大于使用受控压力获得的值。在肾脏表面同时具有肾小球和传出小动脉的六个肾单位中，在传出小动脉血液采集期间监测肾小球毛细血管压力（PGC）。应用广泛变化的吸气压力，PGC 变化高达 42 mmHg，这表明吸气压力不当会改变肾小球压力和流量，从而改变滤过分数和 CE。因此，与肾近端小管不同，一些大鼠肾传出小动脉不具有 Starling 电阻器的功能，这反过来可能解释了一些研究人员最近报告的 CE 值的广泛变异性。
Interglomerular heterogeneity of filtration fraction among superficial nephrons. The variance (S2inter-G) in protein concentration (CE) of plasma samples collected by micropuncture from randomly chosen surface efferent arterioles was compared to the variance (S2intra-G) of samples collected and re-collected from the same efferent arterioles in 23 Munich-Wistar rats. During efferent arteriolar blood collection, an oil droplet was maintained with gentle suction downstream to the collection pipette to avoid disturbance of natural glomerular blood outflow. S2inter-Gaveraged 0.067 ± 0.014 (SE), a value comparable to mean S2intra-G(0.075 ± 0.016, P > 0.50), indicating that the degree of interglomerular heterogeneity in the value of filtration fraction is too small to detect with this micropuncture technique. When ten additional samples were collected using uncontrolled suction pressure, S2inter-Gaveraged 1.15 ± 1.30, a value markedly greater than that obtained with controlled pressure. In six nephrons which possessed both glomeruli and efferent arterioles on the surface of the kidney, glomerular capillary pressure (PGC) was monitored during efferent arteriolar blood collection. Applying widely varied suction pressure, PGCchanged as much as 42 mmHg, suggesting that improper suction pressure can alter glomerular pressures and flows, hence filtration fraction and CE. Thus, unlike renal proximal tubules, some of the rat renal efferent arterioles do not function as Starling resistors, which may, in turn, account for the wide variability in CEvalues reported recently by some investigators.