厄贝沙坦与氢氯噻嗪联用在肾性高血压大鼠体内药动学-药效学关系研究

目的:应用药动学-药效学结合模型研究厄贝沙坦与氢氯噻嗪联用在肾性高血压大鼠体内单剂量及多剂量用药时的药动学-药效学关系。方法:将SD大鼠制备成2肾1夹型肾性高血压模型,给大鼠单剂量或多剂量灌胃给药,分别于第1天和第8天连续的预定时间点测定血药浓度,同时测定动脉收缩压(SBP)和动脉舒张压(DBP)等药物效应,建立效应室药动学-药效学结合模型并计算相关的药动学和药效学参数。对单用、联用及单剂量、多剂量的药动学-药效学规律进行定量研究。结果:厄贝沙坦的药动学特征呈二室模型,氢氯噻嗪在非稳态和稳态条件下均未改变厄贝沙坦的药动学参数,而在稳态条件下,厄贝沙坦可增高氢氯噻嗪的血药浓度及曲线下面积。厄贝沙坦和氢氯噻嗪联用降压效应优于单用的效应。药物效应和效应室浓度之间符合Sigmoid-Emax药效学模型。单剂量下药物效应与血药浓度间存在滞后现象,多剂量下滞后现象消失。Emax、EC50、Keo等药效学参数在厄贝沙坦组和两药联用组之间的差异有统计学意义。结论:建立了PK-PD定量数学模型研究厄贝沙坦和氢氯噻嗪联用在大鼠体内单剂量和多剂量用药后药动学-药效学(暴露-反应)关系的规律,并提供了相关的药动学和药效学参数,可为临床合理用药提供参考依据。     

苦参碱的人体药代动力学

建立了人血清苦参碱的高效液相色谱分析方法,此法回收率为99.1～102.2%,日内精密度RSD<4%,日间RSD<6%。血药浓度在1.25～40.0μg·mL^-1范围内呈线性关系(r=0.9997)。8名健康志愿者iv苦参碱6ms·kg^-1后,药代动力学过程符合二室模型。收集其中6名志愿者尿液,32h尿中原形药物排泄率为52.75%,肾清除率为143.79ml·min^-1。     

厄贝沙坦在健康志愿者体内的药代动力学-药效学结合模型

目的研究厄贝沙坦在健康志愿者体内的药代动力学-药效学结合模型,探讨其临床药效学特征。方法18例健康志愿者厄贝沙坦片口服给药,测定血药浓度,同时测量收缩压(SBP)、舒张压(DBP)及心率(HR)等药效指标。计算厄贝沙坦的药动学参数,并根据sheiner效应室模型理论,计算药效学参数。结果厄贝沙坦的血药浓度时间曲线呈二室模型;厄贝沙坦抑制SBP和DBP的效应滞后于血药浓度,药效与血药浓度之间存在逆时针滞后环,药效和效应室浓度的关系符合SigmoidEmax模型。厄贝沙坦抑制SBP和DBP的药效学参数Emax分别为(14.8±1.5)和(9.8±2.1)mmHg,EC50分别为(0.29±0.11)和(0.18±0.07)mg·L-1,Keo分别为(0.62±0.09)和(0.68±0.07)h-1。结论建立了厄贝沙坦在健康者体内的药代动力学-药效学结合模型,有利于临床合理用药。     

酮洛芬β-CD包合物在兔体内药代动力学—药效动力学研究

为了解药物经β-CD包合后的生物体内性质建立了HPLC-UV法以测定酮洛芬在家兔体内的血药浓度。用酵母诱导家兔的发热反应,考察酮洛芬β-CD包合物与其单体的药代动力学—药效动力学(PK-PD)。结果表明:建立的HPLC-UV法简便可行;酮洛芬β-CD包合物在分布相T_1/2α为0.4h,而其单体的T_1/2α为0.56h,反映了包合后酮洛芬吸收更快;在效应—浓度—时间曲线上,包合后的酮洛芬早期效应略高;酮洛芬给药后的效应峰值滞后于血药浓度峰值,提示药物的效应室在外周室。     

康艾注射液和苦参素注射液在大鼠体内的药代动力学

目的：研究康艾注射液（复方）和苦参素注射液（单方）中氧化苦参碱在大鼠体内的药代动力学,考察康艾注射液中多种成分对氧化苦参碱体内过程的影响。方法：SD大鼠尾静脉注射给药,给药剂量为200mg&#183;Kg^-1（按氧化苦参碱计）,心脏采血,采用高效液相色谱法测定血清中氧化苦参碱和其活性代谢物苦参碱的浓度。药-时数据采用3P97软件进行处理。结果：康艾注射液和苦参素注射液中氧化苦参碱及苦参碱在大鼠体内的药动学均符合二房室模型。     

HPLC-MS法测定Beagle犬血浆中氧化苦参碱及其药代动力学

目的 :建立Beagle犬血浆中氧化苦参碱的LC MS测定法 ,测定它的绝对生物利用度。方法 :Beagle犬 6只 ,随机分为 2组 ,采用单剂量双周期自身交叉设计 ,分别给犬单剂量静脉注射或灌胃氧化苦参碱 ,用LC MS法测定给药后的血浆中药物浓度。结果 :氧化苦参碱在 2～ 5 0 0 0 μg·L-1的范围内呈良好的线性关系 (r =0 .9990 ) ,最低检出限达0 .6 μg·L-1,日内和日间误差均小于 4 .2 % ,方法回收率大于 96 .7% ;氧化苦参碱的药 时数据符合二室模型 ,Cmax为 2 .4 2± 0 .97μg·L-1,Tmax为 1.0± 0 .3h ,T1 2 β为 5 .5 4± 1.5 8h ,AUC0→∝ 为 6 .12± 1.0 8μg·L-1·h-1,绝对生物利用度为 (19.4± 9.0 1) %。结论 :该法灵敏、简单 ,专属性强 ;氧化苦参碱在Beagle犬体内绝对生物利用度较低     

7-(4-氯苄基)-7,8,13,13a-四氢小檗碱氯化物在犬体内的药代动力学和药效学

以 QT校正 ( QTc)延长百分率为效应指标 ,用药代动力学 -药效学 ( PK- PD)结合模型对家犬 iv1 .0 ,2 .0 mg· kg-1的 7- ( 4 -氯苄基 ) - 7,8,1 3,1 3a-四氢小檗碱氯化物 ( CPU860 1 7)后在体内的处置和效应作定量分析 .给家犬 iv CPU860 1 7后的血药浓度经时过程符合二房室模型 ,药物的效应与效应室浓度之间的关系符合 S形 Emax模型 .CPU860 1 7的 PK- PD性质在所用剂量范围内均为非剂量依赖性 .     

氧化苦参碱缓释片在犬体内的药物动力学

研究氧化苦参碱缓释片在家犬体内单剂量和多剂量口服给药后的药物动力学.采用HPLC法测定家犬口服氧化苦参碱缓释片和普通胶囊后的血药浓度,结果表明,氧化苦参碱药-时曲线符合双室模型特征.单剂量口服缓释片和胶囊后Ka分别为(0.60±0.11)和(1.22±0.11)h-1;Tmax分别为(2.83±0.26)和(1.58±0.20)h;Cmax分别为(1.96±0.73)和(3.06±0.42)μg/ml,氧化苦参碱缓释片相对胶囊生物利用度F为(90.22±5.7)%.多剂量口服两种制剂4天后达稳态,波动系数分别为(1.37±0.35)和(1.59±0.40).     

麝香酮在大鼠、家兔和狗体内的药代动力学

麝香酮在大鼠体内的药时过程符合二室开放模型,在家兔和狗体内的药时过程则符合三室开放模型。大鼠、家兔和狗之间的药代动力学过程存在着显著的种属差异,大鼠iv麝香酮12,18和24 mg/kg三种剂量间的药代动力学主要参数无显著性差异。iv给药大鼠的T_1/2B为118.1～131.2min。家兔和狗的T_1/2B分别为24.9和30.0 min,T_1/2γ分别为331.9和366.4 min。大鼠、家兔和狗三b种动物的V_ss分别为23.0,51.7和7.3 L/kg.V_c分别为2.33,2.13和0.38 L/kg。     

氧化苦参碱注射液的人体药代动力学

氧化苦参碱(oxymatrine)是从豆科槐属植物苦豆子及苦参根中提取分离得到的一种双稠哌啶衍生物，现代药理学研究表明它有强心、抗心率失常、抗炎抗肿瘤等作用^[1,2]纠。近年来它还被用于治疗乙型肝炎，取得良好的效果。氧化苦参碱在动物体内的药代动力学研究已有报道^[3-5]，但人体药代动力学研究尚未见报道。本实验用反相离子对HPLC法测定了人血浆中的氧化苦参碱浓度，并对氧化苦参碱注射液进行了健康人体的药代动力学研究，为临床用药提供依据。     

Population pharmacokinetic-pharmacodynamic modelling of angiotensin receptor blockade in healthy volunteers

OBJECTIVE: To compare the pharmacokinetic and pharmacodynamic characteristics of angiotensin II receptor antagonists as a therapeutic class. DESIGN: Population pharmacokinetic-pharmacodynamic modelling study. METHODS: The data of 14 phase I studies with 10 different drugs were analysed. A common population pharmacokinetic model (two compartments, mixed zero- and first-order absorption, two metabolite compartments) was applied to the 2685 drug and 900 metabolite concentration measurements. A standard nonlinear mixed effect modelling approach was used to estimate the drug-specific parameters and their variabilities. Similarly, a pharmacodynamic model was applied to the 7360 effect measurements, i.e. the decrease of peak blood pressure response to intravenous angiotensin challenge recorded by finger photoplethysmography. The concentration of drug and metabolite in an effect compartment was assumed to translate into receptor blockade [maximum effect (Emax) model with first-order link]. RESULTS: A general pharmacokinetic-pharmacodynamic (PK-PD) model for angiotensin antagonism in healthy individuals was successfully built up for the 10 drugs studied. Representatives of this class share different pharmacokinetic and pharmacodynamic profiles. Their effects on blood pressure are dose-dependent, but the time course of the effect varies between the drugs. CONCLUSIONS: The characterisation of PK-PD relationships for these drugs gives the opportunity to optimise therapeutic regimens and to suggest dosage adjustments in specific conditions. Such a model can be used to further refine the use of this class of drugs.     

Impact of pharmacodynamic variability on drug delivery(1)

Modern pharmaceutical delivery systems are intended to produce plasma drug concentration versus time profiles that result in optimum therapeutic efficacy and a minimum of drug concentration-dependent adverse effects. To accomplish this requires that the drug delivery rate and temporal profile be based on the pharmacokinetic and pharmacodynamic characteristics of the specific medicinal agent. Pharmacokinetic and pharmacodynamic parameters are subject to considerable interindividual variability. Whereas the importance of pharmacokinetic variability is generally recognized, the significance of pharmacodynamic variability (i.e., variability in the relationship between effect intensity and drug concentration) is not as widely appreciated. Pharmacodynamic variability is typically quite large, reproducible, and often substantially exceeds the relative magnitude of pharmacokinetic variability. This article consists of a review of how to assess pharmacodynamic variability, clinical examples of pharmacodynamic variability of drugs with a wide range of indications, and an outline of mechanisms of pharmacodynamic variability.     

构建沙格列汀PK/PD模型——模拟其在健康人群和肝损伤患者的药动学和药效学

在本次研究中,我们旨在开发和评价沙格列汀的全身生理药代动力学(WB-PBPK)/药效学(PD)模型,模拟其在健康成人及肝功能损害患者中的药代动力学和药效学特性,为特殊患者的临床药学研究提供新方法.基于文献中获取的如logD和血浆蛋白结合率等药物特征参数,建立WB-PBPK模型和PD模型.将模拟所得的血药浓度-时间曲线及...     

Pharmacokinetic/pharmacodynamic analysis of neutrophil proliferation induced by rhG-CSF in patients receiving antineoplastic drugs

In the present study, we analyzed the effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on neutrophil counts in cancer patients undergoing chemotherapy using a previously developed pharmacokinetic/pharmacodynamic model.(7)) The time profiles of neutrophil counts in blood after repeated administration of rhG-CSF to lung cancer patients undergoing chemotherapy could be analyzed by this model by considering the inhibition of neutrophil production by antineoplastic drugs. Although deviation was observed between the predicted and observed neutrophil counts in ovarian cancer patients, it may be possible to use this model for determining a rational dosage regimen of rhG-CSF for patients undergoing chemotherapy.     

以药效学参数为终点指标的生物等效性评价方法

生物等效性是仿制药一致性评价的重要阶段。以药效学参数为终点指标评价生物等效性方法逐渐引发关注。在药动学方法无法实施或药动学参数无法灵敏地体现两药差异的情况下,选择合理的药效学参数作为终点指标可有效地评价药品之间的差异。参考相关指南、法规及文献,系统地阐述药效学方法的适用条件,根据量效曲线选择终点指标,终点参数分析以及具体药物方法设计等,为相关研究提供参考和帮助。     

Quantifying pharmacodynamic interaction between atenolol and valsartan

We used mathematical modeling in order to determine the pharmacodynamic relationship between antihypertensive drugs atenolol and valsartan, by evaluating their effects on heart rate (HR), systolic blood pressure (SP) and diastolic blood pressure (DP). A group of twelve healthy male volunteers received a single oral dose of 100 mg of atenolol and 160 mg of valsartan, both separately and in combination. Pharmacokinetic (PK), pharmacokinetic/pharmacodynamic (PK/PD) and pharmacodynamic (PD) systems were proposed and PD model of atenolol and valsartan concentration-time profiles and PK/PD model of blood pressure and heart rate effects after administration of single doses of atenolol and valsartan and their combination were constructed. Parameters of PD system, such as gain and mean effect time, were obtained by analysis of PK and PK/PD systems. Modeling of PK and PK/PD systems and their analysis to obtain the PD results could considerably change the view o treatment of individual diseases in terms of greater knowledge of pharmacokinetics and pharmacodynamics of drugs.     

Pharmacokinetic and pharmacodynamic of irbesartan in renal hypertensive dogs under non-steady-state and steady-state conditions.

The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of irbesartan in renal hypertensive dogs under non-steady-state and steady-state conditions using pharmacokinetic-pharmacodynamic (PK/PD) modeling. Drugs were administered intragastrically to renal hypertensive dogs, plasma drug concentration was determined by HPLC method and Pharmacologic effects, including SBP, DBP, dp/dtmax and LVSP, were measured simultaneously. AT II, Aldosterone (ALD) and Endothelin (ET) were also used as measurement of effect. The PK and PD data were quantitatively analyzed according to the PK/PD model theory. The pharmacokinetic profiles of irbesartan conformed to a two-compartment open model. There was hysteresis loops between effects and plasma concentrations under non-steady-state condition. The relationship between effects and effect compartment concentrations (Ce) could be represented by the Sigmoid-Emax model. The Hysteresis loops disappeared under steady-state condition with more rapidly attainment of maximum concentration and effect. There were certain difference of pharmacokinetic and pharmacodynamic properties between non-steady-state and steady-state condition.     

PHARMACOKINETIC AND PHARMACODYNAMIC ANALYSIS OF (E)-2-ENE VALPROYL DERIVATIVES OF GLYCINE AND VALPROYL DERIVATIVES OF NIPECOTIC ACID

GABA is a major inhibitory neurotransmitter in mammals, whose uptake in glial cells is inhibited by nipecotic acid. In addition to GABA, glycine is an important inhibitory neurotransmitter. Valproic acid (VPA) is one of the four established antiepileptics and (E)-2-ene valproic acid ( (E)-2-ene VPA) is its major active metabolite. The described structure–pharmacokinetic–pharmacodynamic relationship (SPPR) study explored the possiblity of utilizing valproyl derivatives of glycine and nipecotic acid as new antiepileptics. The pharmacokinetics and pharmacodynamics (anticonvulsant activity and neurotoxicity) of the following conjugation products were investigated: (E)-2-ene valproyl glycinamide (between (E)-2-ene VPA and glycinamide) and valproyl nipecotic acid and valproyl nipecotamide (between VPA and nipecotic acid). Out of the investigated compounds only (E)-2-ene valproyl glycinamide showed a good anticonvulsant profile in both mice and rats due to its better pharmacokinetic and pharmacodynamic profile. (E)-2-ene valproyl glycinamide was more potent than VPA and showed an activity and a safety margin similar to those of its analogous compound valproyl glycinamide. The investigated valproyl derivatives did not operate as chemical drug delivery systems (CDDSs) of glycine or nipecotic acid, but, rather, acted as drugs on their own. (E)-2-ene valproyl glycinamide was partially excreted unchanged in the urine (f_e=7·4%), while its urinary metabolite was (E)-2-ene valproyl glycine. Unlike the new antiepileptic tiagabine, in which nipecotic acid is attached to 4, 4-di-(3-methylthien-2-yl)-3-butenyl and yields an active compound, the conjugation between nipecotic acid or its amide and VPA yielded inactive entities. In contrast to nipecotic acid, the conjugation between VPA or (E)-2-ene VPA and glycinamide gave two active compounds with similar pharmacokinetic and pharmacodynamic profiles.