一室模型药物吸收计算的概率论法  

Method of probability theory for calculating the absorption rate of drug in one-compartmental model

作　　者：李进文[1] 

机构地区：[1]兰州军区乌鲁木齐总医院药剂科

出　　处：《中国临床药理学与治疗学》2012年第1期59-63,共5页Chinese Journal of Clinical Pharmacology and Therapeutics

摘　　要：目的:从概率论角度为吸收动力学研究提供两种具体方法。方法:在一室模型时,药物分子从给药部位进入体循环和从体内消除的过程为相互独立的随机过程。将一次血管外给药后的总滞留时间(Th)视为在给药部位的滞留时间(Tf)与在体内的滞留时间(Tg)之和,Tf与Tg相互独立,且Th、Tf及Tg均为非负连续型随机变量。根据卷积公式及一室模型特征,得到一室模型药物吸收计算的概率论方法:概率法(A法)与数值反卷积分法(B法)。结果:概率论方法所需条件与Wagner-Nelson(W-N)法一致。A法所求吸收分数的准确度与W-N法相同。在已知消除速率常数K的准确值时,B法所求吸收分数的准确度低于W-N法,但B法尚可推测出同一药物注射剂型在血管内快速给药后的概率密度函数及相关信息。在K估计值有误差(±10%)时,B法所求吸收分数的准确度略高于W-N法。结论:概率论方法可用于计算吸收分数及有关概率。ABSTRACT AIM： Based on probability theory, two concrete methods for absorption kinetics were proposed in one-compartmental model. METHODS： After an extravascular administra- tion of drug, total resident time （Th） was regar- ded as sum of the resident time in site of administration （Tf） and the resident time in body （Tg）. Not only are Tf and Tg independent each other, Tf, Tg and Th are nonnegative, continu- ous random variables also. According to convo- lution formula and characterization of one-com- partmental model （ exponential distribution）, methods of probability theory for calculating the absorption rate of drug were obtained. These methods were composed of probability method （A approach ） and numerical deconvolution method （B approach）. RESULTS： The essential conditions of method of probability theory werein accordance with that of Wagner-Nelson （W- N） formula. The accuracy of A approach was i- dentical with that of W-N formula. As long as the accurate value of first-order elimination rate constant （K） can be estimated, the accuracy of B approach was inferior to that of W-N formula. In case K value with relative error （-t-10%） was calculated, the accuracy of B approach was slightly superior to that of W-N formula. CON- CLUSION： Method of probability theory can be suggested to estimate the percentage of drug ab- sorbed and the concerned probability.

关 键 词：药物动力学 一室模型 吸收动力学 概率论 概率 随机向量 卷积-反卷积 概率密度函数 分布函数 

分 类 号：R969[医药卫生—药理学]