Effects of hematocrit on oxygenation of the isolated perfused rat liver.
Effects of hematocrit on oxygenation of the isolated perfused rat liver.
复制标题
血细胞比容对离体灌注大鼠肝脏氧合的影响。
DOI：
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发表时间：
1983
影响因子：
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通讯作者：
Walter F. Ward
中科院分区：
文献类型：
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作者：
G. Riedel;J. Scholle;A. P. Shepherd;Walter F. Ward
离体灌注大鼠肝脏广泛用于肝功能的代谢和内分泌研究，但关于此类制剂氧合不足的数据很少。此外，离体的大鼠肝脏通常被剥夺动脉供应，并通过肝门静脉用低血细胞比容或无细胞溶液灌注。为了研究供氧的功效，我们确定了血细胞比容对耗氧量和灌注液流量之间关系的影响。然后我们尝试定义肝氧合达到最大时的血细胞比容。用戊巴比妥钠麻醉的雄性大鼠的肝脏通过门静脉灌注悬浮在克雷布斯-林格-碳酸氢盐缓冲液中的新鲜犬红细胞。以不同的流速进行灌注，并确定灌注液流量和摄氧量之间的关系。当流速高于 100 ml X min-1 X 100 gliver-1 时，摄氧量与流量无关，但低于该值时，流量受到限制，无论血细胞比容是 10%、20% 还是 40%。为了确定肝摄氧量的最佳血细胞比容，肝门静脉和肝静脉压力分别保持在 10 和 0 mmHg。血细胞比容从 80% 逐步降低至 10%。随着血细胞比容下降，血流量呈指数增加，而摄氧量增加到最大值约 20%。结论是，大约 20% 的血细胞比容提供了血流和携氧能力的最佳组合，同时维持生理灌注压，例如 10 mmHg。
The isolated perfused rat liver is used ubiquitously for metabolic and endocrine studies of hepatic function, yet few data are available regarding the inadequacy of the oxygenation of such preparations. Moreover, the isolated rat liver is usually deprived of its arterial supply and perfused via the hepatic portal vein with low-hematocrit or cell-free solutions. To investigate the efficacy of the oxygen supply, we determined the effect of hematocrit on the relation between oxygen consumption and perfusate flow. We then attempted to define a hematocrit at which hepatic oxygenation was maximal. Livers of male rats anesthesized with pentobarbital sodium were perfused via the portal vein with fresh canine red blood cells suspended in Krebs-Ringer-bicarbonate buffer. Perfusions were carried out at various flow rates, and the relation between perfusate flow and oxygen uptake was determined. At flow rates above 100 ml X min-1 X 100 g liver-1, oxygen uptake was independent of flow but below that value was flow limited, regardless of whether the hematocrit was 10, 20, or 40%. To determine the optimal hematocrit for hepatic oxygen uptake, hepatic portal venous and hepatic venous pressures were held at 10 and 0 mmHg, respectively. The hematocrit was lowered in steps from 80 to 10%. Blood flow increased exponentially as hematocrit fell while oxygen uptake increased to a maximum at approximately 20%. It is concluded that an hematocrit of approximately 20% provides the optimal combination of blood flow and oxygen-carrying capacity while maintaining physiological perfusion pressures, e.g., 10 mmHg.