Sickling times of individual erythrocytes at zero Po2.
Sickling times of individual erythrocytes at zero Po2.
复制标题
Po2 为零时单个红细胞的镰刀化时间。
DOI：
10.1172/jci108149
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发表时间：
1975
期刊：
影响因子：
--
通讯作者：
R. Hochmuth
中科院分区：
文献类型：
--
作者：
H. Zarkowsky;R. Hochmuth
采用快速反应平行板流道研究了二亚硫酸钠突然脱氧时红细胞镰状反应的动力学。将红细胞记录在16mm胶片或录像带上，并及时目视追踪。通过形态学标准确定镰状细胞病。在这些研究中使用的流速下，镰状结的速率是一个反应受限的过程。在镰状细胞发病前，没有细胞变形能力丧失或膜闪烁。镰状细胞（SS）和性状细胞（AS）在室温等渗缓冲液中的典型镰刀化时间分别为2.0 s和70 s。增加缓冲液渗透压可缩短镰状反应时间，在低渗条件下镰状反应时间延长。在pH 6.4和7.0之间，50%的原始盘状细胞变为镰状所需的时间变化不大（t50）；而在pH值7.4和7.6之间，t50显著增加。全群AS和SS红细胞经离心分离成三个部分。各组分t50从上到下逐渐降低，与平均红细胞血红蛋白浓度（MCHC）升高相一致。t50随着温度从13度增加到34度而下降，这种温度效应在渗透诱导MCHC减少的细胞中更为明显。提出了红细胞镰状细胞的两步过程：初始滞后期，在此期间内部粘度很少或没有变化，然后是细胞变形的快速阶段。滞后期会因MCHC、pH和温度的变化而改变。
A rapid-reaction parallel-plate flow channel was used to study the kinetics of erythrocyte sickling upon sudden deoxygenation with sodium dithionite. The erythrocytes were recorded on 16-mm film or video tape and visually tracked in time. Sickling was identified by morphologic criteria. At the flow rate used in these studies, the rate of sickling was a reaction-limited process. There was no loss of cellular deformability or membrane flicker before the onset of sickling. Typical sickling times for sickle (SS) cells and trait (AS) cells at room temperature in isotonic buffer were 2.0 and 70 s, respectively. Increasing the buffer osmolality resulted in shorter sickling times and under hypotonic conditions the time required for sickling was prolonged. Between pH 6.4 and 7.0 there was little change in the time required for 50% of the originally discoidal cells to sickle (t50); whereas a marked increase in t50 occurred between pH 7.4 and 7.6. Whole populations of AS and SS erythrocytes were separated into three fractions after centrifugation. The t50 of the fractions progressively decreased from top to bottom, which paralleled an increase in mean corpuscular hemoglobin concentration (MCHC). The t50 decreased as the temperature was increased from 13 degrees to 34 degrees C. This temperature effect was more pronounced for cells that had osmotically induced reductions in MCHC. A two-step process for erythrocyte sickling is proposed: an initial lag phase, during which there is little or no change in internal viscosity, followed by a rapid phase of cellular deformation. The lag phase is altered by changes in MCHC, pH, and temperature.