Differences and similarities in albumin and red blood cell flows through cerebral microvessels.
Differences and similarities in albumin and red blood cell flows through cerebral microvessels.
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白蛋白和红细胞流经脑微血管的差异和相似之处。
DOI：
10.1152/ajpheart.1992.262.5.h1515
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Fenstermacher,J
中科院分区：
文献类型：
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作者：
Tajima,A;Nakata,H;Lin,SZ;Acuff,V;Fenstermacher,J
在清醒的 Sprague-Dawley 大鼠中测试了脑实质中的微血管持续被血浆灌注但间歇性被红细胞 (RBC) 灌注的假设。测量 15 秒至 30 分钟期间放射性碘标记的血清白蛋白 (RISA) 以及 51Cr 和 55Fe 标记的红细胞的微血管分布体积。通过碘安替比林技术评估局部脑血流量（LCBF）。从 15 秒起，研究的 12 个区域的 RISA 和 RBC 分布量保持恒定。这些数据符合连续血浆流和间歇性红细胞流的模型（因此支持该假设），但它们也与其他模型一致，例如血浆和红细胞通过所有灌注微血管的连续流。与 LCBF 平行，不同脑区的微血管血容量差异超过 10 倍。相对于动脉血细胞比容，微血管血细胞比容较低，这表明红细胞通过实质微血管的速度比RISA更快。这可能是 Fahraeus 效应和间歇性红细胞流动的结果。
The hypothesis that microvessels in brain parenchyma are continuously perfused by plasma but intermittently perfused by red blood cells (RBCs) was tested in awake Sprague-Dawley rats. The microvascular distribution volumes of radioiodinated serum albumin (RISA) and 51Cr- and 55Fe-labeled RBCs were measured for periods from 15 s to 30 min. Local cerebral blood flow (LCBF) was assessed by the iodoantipyrine technique. The RISA and RBC distribution volumes were constant in the 12 areas studied from 15 s onward. These data fit a model of continuous plasma flow with intermittent RBC flow (and thus support the hypothesis), but they are also consistent with other models, e.g., continuous flow of both plasma and RBCs through all perfused microvessels. In parallel with LCBF, microvascular blood volume varied greater than 10-fold among brain areas. Relative to arterial hematocrit, microvascular hematocrits were low, which indicates that the passage of RBCs through parenchymal microvessels is more rapid than that of RISA. This could be the result of both the Fahraeus effect and intermittent RBC flow.