Lin J H, Sugiyama Y, Awazu S, Hanano M
J Pharmacokinet Biopharm. 1982 Dec;10(6):637-47. doi: 10.1007/BF01062545.
An important parameter used in physiologically based pharmacokinetic models is the partition coefficient (Kp), which is defined as the ratio of tissue drug concentration to the concentration of drug in the emergent venous blood of the tissue. Since Kp is governed by reversible binding to protein and other constituents in blood and tissue, an attempt was made here to estimate the Kp values for a model drug ethoxybenzamide (EB) by means of in vitro binding studies and to compare these Kp values to those obtained from in vivo kinetic parameters observed following the administration of EB by two different routes, i.e., i.v. bolus injection and constant rate infusion. The Kp values obtained by using these three different methods were in reasonably good agreement suggesting that binding data obtained in vitro can successfully be used to estimate in vivo distribution.
基于生理的药代动力学模型中使用的一个重要参数是分配系数（Kp），其定义为组织药物浓度与该组织流出静脉血中药物浓度的比值。由于Kp受药物与血液和组织中蛋白质及其他成分的可逆结合所支配，因此本文尝试通过体外结合研究来估算模型药物乙氧苯酰胺（EB）的Kp值，并将这些Kp值与通过两种不同给药途径（即静脉推注和恒速输注）给予EB后观察到的体内动力学参数所获得的Kp值进行比较。使用这三种不同方法获得的Kp值相当吻合，这表明体外获得的结合数据可成功用于估算体内分布情况。
