Glasinovic J C, Dumont M, Duval M, Erlinger S
Am J Physiol. 1975 Nov;229(5):1455-60. doi: 10.1152/ajplegacy.1975.229.5.1455.
The purpose of this study was to determine the initial space of distribution of [14C]erythritol (mol wt 122) and [14C]mannitol (mol wt 182) in the liver of the dog by the single-injection, multiple-indicator-dilution method. 22Na was used as the extracellular indicator and tritiated water (THO) was used as total liver water indicator. The indicators were simultaneously injected into the portal vein of anesthetized dogs and dilution curves were obtained at the outflow from the hepatic vein. It was found that hepatic venous dilution curves of [14C]erythritol and THO were practically identical in all experiments. In contrast, the dilution curves of [14C]mannitol were generally distinct from those of THO. Analysis of [14C]mannitol-dilution curves according to Goresky suggested that the observed difference between this solute and THO was the result of a limited permeability of the sinusoidal membrane to mannitol. It is concluded that [14C]erythritol has instantaneous and practically unrestricted access to total liver water. This finding supports the validity of using erythritol as a liver cell water marker. A larger solute, [14C]mannitol, has restricted access to total liver cell water because of a permeability barrier in the sinusoidal liver cell membrane, but its diffusion into the hepatocyte is also very rapid.
本研究的目的是通过单次注射、多指示剂稀释法，确定[14C]赤藓糖醇（分子量122）和[14C]甘露醇（分子量182）在犬肝脏中的初始分布空间。以22Na作为细胞外指示剂，以氚水（THO）作为肝脏总水量指示剂。将指示剂同时注入麻醉犬的门静脉，并在肝静脉流出端获得稀释曲线。发现在所有实验中，[14C]赤藓糖醇和THO的肝静脉稀释曲线实际上是相同的。相比之下；[14C]甘露醇的稀释曲线通常与THO的稀释曲线不同。根据戈列斯基的方法对[14C]甘露醇稀释曲线进行分析表明，该溶质与THO之间观察到的差异是由于肝血窦膜对甘露醇的通透性有限所致。得出的结论是，[14C]赤藓糖醇可立即且几乎不受限制地进入肝脏总水量。这一发现支持了使用赤藓糖醇作为肝细胞水标志物的有效性。一种较大的溶质，即[14C]甘露醇，由于肝血窦细胞膜中的通透性屏障，进入肝脏总细胞水量受到限制，但其向肝细胞内的扩散也非常迅速。
