Burczynski F J, Cai Z S
Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, Canada.
Am J Physiol. 1994 Sep;267(3 Pt 1):G371-9. doi: 10.1152/ajpgi.1994.267.3.G371.
The clearance ratio test has been used to determine whether hepatocytes isolated from female rat livers facilitate the dissociation rate of albumin-palmitate complexes. This test requires knowledge of the clearance rate and unbound palmitate fraction at two protein concentrations. The unbound fractions have been estimated using the heptane-water partition ratio method. These fractions were determined to deviate from the expected linear relationship because of radiolabeled impurities that were still present after purification of the [3H]palmitic acid. With the use of experimentally determined partition ratio values, the palmitate clearance ratios were statistically greater than those predicted by the diffusion-reaction model at albumin concentration combinations above 99 microM/49 microM. Experimental clearance rates also exceeded those predicted by the diffusion-reaction model, but only at albumin concentrations greater than 198 microM. These data support the proposal that hepatocytes facilitate the dissociation of albumin-palmitate complexes at high albumin concentrations.
清除率试验已被用于确定从雌性大鼠肝脏分离出的肝细胞是否会促进白蛋白 - 棕榈酸酯复合物的解离速率。该试验需要了解两种蛋白质浓度下的清除率和未结合棕榈酸酯分数。未结合分数已使用庚烷 - 水分配比方法进行估算。由于在[3H]棕榈酸纯化后仍存在放射性标记杂质，这些分数被确定偏离预期的线性关系。使用实验确定的分配比值，在白蛋白浓度组合高于99 microM/49 microM时，棕榈酸酯清除率在统计学上高于扩散 - 反应模型预测的值。实验清除率也超过了扩散 - 反应模型预测的值，但仅在白蛋白浓度大于198 microM时。这些数据支持了肝细胞在高白蛋白浓度下促进白蛋白 - 棕榈酸酯复合物解离的提议。
