呋喃苯胺酸在人体内的药动—药效学研究

本文研究了利尿药呋喃苯胺酸(速尿) 在人体内的药动—药效学。4名健康受试者分别口服了5,10,20及40 mg剂量的呋喃苯胺酸,测定了各时间的尿药数据,利尿量以及钠与钾离子排泄的增量。实验数据用电子计算机作了非线性最小二乘法模型嵌合处理,表明该药在体内符合双室开放模型。3 h内的总利尿量、总Na~++K~+的排泄增量与给药剂量的对数之间呈现良好的线性关系。给药后各时间的累积尿药量与累积药效之间符合Hill方程式。还推出了该药的排泄速度与利尿速度之间的一个关系式,与实验数据十分吻合。     

呋喃苯胺酸在人体内的药动—药效学研究

本文研究了利尿药呋喃苯胺酸(速尿) 在人体内的药动—药效学。4名健康受试者分别口服了5,10,20及40 mg剂量的呋喃苯胺酸,测定了各时间的尿药数据,利尿量以及钠与钾离子排泄的增量。实验数据用电子计算机作了非线性最小二乘法模型嵌合处理,表明该药在体内符合双室开放模型。3 h内的总利尿量、总Na⁺+K⁺的排泄增量与给药剂量的对数之间呈现良好的线性关系。给药后各时间的累积尿药量与累积药效之间符合Hill方程式。还推出了该药的排泄速度与利尿速度之间的一个关系式,与实验数据十分吻合。     

药动学-药效学结合模型的研究进展

本主要对近年来药动学．药效学结合模型在模型建立、药理学、毒理学、临床应用及新药研发等方面的进展进行了综述，并展望其发展前景。     

卡维地洛人体药动学与药效学结合模型研究

采用间接药效学模型和效应室模型两种药效学模型分别进行卡维地洛药动学与药效学关系研究, 比较两种药效学模型的拟合程度。高效液相色谱法 (荧光) 测定20名健康志愿者单次口服20 mg卡维地洛片后卡维地洛经时血药浓度, 以DAS 2.0实用药动学计算程序计算卡维地洛药动学参数。同时测定给药前后动脉收缩压和舒张压, 计算降压效果。卡维地洛片主要药动学参数t_1/2为 (4.56 ± 2.56) h, C_max为 (46.29 ± 21.07) ng·mL^-1, AUC_0-∞为 (173.76 ± 87.36) ng·mL^-1·h。间接药效模型主要参数K_in为 (0.41 ± 0.31) % h^-1, K_out为 (0.40 ± 0.26) h^-1, IC₅₀为 (24.40 ± 21.10) ng·mL^-1, AUE为 (3.82 ± 1.46) % h。效应室模型主要参数K_e0为 (0.35 ± 0.27) h^-1, EC₅₀为 (24.30 ± 24.30) ng·mL^-1, AUE为 (5.65 ± 2.54) % h。该方法可用于卡维地洛片人体药动学研究。由AIC值可知, 效应室模型可更好的应用于卡维地洛药动学-药效学结合研究。

     

药动学-药效学结合模型的研究进展及应用

目的 综述药动学-药效学(PK-PD)结合模型的研究进展。方法 对近十年来国内外发表的具有代表性的相关文章进行分析、整理和归纳,总结PK-PD结合模型的类型、程序及应用。结果 PK-PD结合模型有4种类型,其在新药研发,个体化给药和临床检测等方面都有广泛的应用,为临床用药提供了有力的指导。结论 PK-PD模型随着研究的深入不断完善,在药物开发和研究中发挥了重要的作用。     

兔体内静脉输注乙酰普鲁卡因胺的药动学—药效学结合模型分析

用药动学-约效学结合模型,对ⅳ乙酰普鲁卡因胺(NAPA)后,进行了药代动力学和药效动力学分析。兔体内NAPA ⅳ后与静脉推注后的药动学参数基本一致;但效应按QT_c延长作为指标,其药效动力学的个别参数有显著性差异。输注后,NAPA的E_max,K_eo,S和EC₅₀分别为120±13.2ms,0.0182±0.007min^-1,2.26±0.93和6.31±0.71μg/ml;推注后,分别为53.6±2.5ms,0.061±0.017min^-1,2.19±0.39和6.21±1.74μg/ml。     

尿酸酶多囊脂质体在大鼠体内的药动学和药效学试验

目的 研究大鼠皮下注射尿酸酶多囊脂质体(UMVLs)的药动学过程;用尿酸酶抑制剂氧嗪酸建立高尿酸血症大鼠模型,考察尿酸酶的体内降尿酸作用.方法 将12只健康♂ SD大鼠随机均分为2组,分别皮下注射UMVLs和游离尿酸酶,测定给药后不同时间点大鼠血清中尿酸酶的活性,用DAS 2.1.1软件计算药动学参数;于大鼠皮下注射氧嗪酸钾建立高尿酸血症大鼠模型,分别于建模1h后于皮下注射UMVLs和游离尿酸酶,建模1、2、3、5、7、9、12、24、36、48、60、72、96 h后测定大鼠血清中尿酸水平.结果 UMVLs和尿酸酶的主要药动学参数AUC0-72h分别为179.13±17.76、87.61±10.54 U·h·L-1,Cmax分别为35.03±2.35、38.26±6.03 U·L-1,Tmax分别为4.00±0.88、1.00±0 h,UOMVLs的相对生物利用度为204.46％±20.27％.结论 UMVLs提高了尿酸酶的生物利用度,并可有效降低高尿酸模型大鼠血清中尿酸水平.     

抗真菌药物的药动学和药效学研究进展

目的:介绍临床常用抗真菌药物的药动学和药效学研究进展,旨在为临床合理用药提供相关依据。方法:查阅国内、外相关文献,进行系统的阅读复习,并进行综合分析。结果:真菌感染发病复杂,诊断困难,预后较差,但是抗真菌药物研发的不断进步,为临床医生用药提供了更多选择,真菌感染的治疗和预后将逐步得到改善。结论:临床常用抗真菌药物的药动学和药效学研究,对于临床合理用药具有重要的指导意义。     

Simultaneous pharmacokinetic and pharmacodynamic modeling

The compartmental model approach previously proposed by Sheiner et al.for the simultaneous characterization of the pharmacokinetics and pharmacodynamics of a drug substance has been rigorously tested and extended in the present report. Pharmacokinetic and pharmacodynamic equations were derived for several commonly used models, as well as alternate models that relate effect to drug concentrations in a peripheral compartment. The versatility and flexibility of these models were tested using simulation and curve-fitting procedures. The utility as well as the limitations of this modeling procedure are discussed.     

三种估算药动学—药效学参数方法的比较及应用

根据三种估算药动学和药效学结合模型参数的方法编制了软件。参数法包括十个药动学模型和三种药效学模型,可以同时求算药动学和药效学参数;非参数药效模型法不必预先假设药效学模型就可估算出反映药物效应的消除速率常数(K_(eo));非参数药效模型法中,药动学模型也用非参数方法描述,只要输入药动—药效数据就可求出K_(ro)。对6例吸入大麻的健康志愿者的药动—药效数据,用以上方法进行验算,结果表明三种方法各有优点,应比较使用。     

美托洛尔在家兔和肾性高血压大鼠体内的药代动力学-药效学结合模型

正常家兔 im1 0 ,1 5mg· kg-1和肾性高血压大鼠 ig美托洛尔 ,研究药物在两种动物体内降低心率和血压效应与药代动力学之间的关系 ,用高效液相荧光检测药物浓度 ,结果显示 :美托洛尔血药浓度时间曲线均符合二室模型 ,其降低心率和血压的最大效应明显滞后于血药浓度 .应用 Sheiner等提出的药代动力学 -药效学结合模型 ,用多维函数一次搜寻法对效应室药物浓度 ( Ce)与抑制心率及降低血压效应进行拟合 ,得出美托洛尔在两种动物体内的Ce和抑制心率效应之间的关系符合 Sigmoid- Emax模型 ,而 Ce 和降低血压效应之间的关系符合 β-功能模型 ,以上效应的预测值和实测值拟合良好 ,因此认为以上数学模型可以应用于动物实验中效应的预测 .     

Population pharmacokinetic and pharmacodynamic model of norvancomycin

去甲万古霉素群体药代动力学与药效学研究@张菁$Institute of Antibiotics, Huashan Hospital, Fudan University!Shanghai 200040, China @张婴元$Institute of Antibiotics, Huashan Hospital, Fudan University!Shanghai 200040, China @施耀国$Institute of Antibiotic     

Pharmacokinetic and pharmacodynamic study of the combination of furosemide retard and triamterene

Summary The pharmacodynamics and pharmacokinetics of the combination of furosemide retard (30 mg)/triamterene (50 mg) were compared with furosemide (30 mg) in 18 healthy male volunteers aged 39.3±6.3 years. After the administration of furosemide the onset of its effect was very rapid, reaching a maximum between 1.5 to 3 h, and followed by rebound after 9 to 10.5 h. In contrast the combination furosemide retard/triamterene showed a protracted course with a duration of effect up to 12 h. The general effect over 12 h of the two preparations was equivalent with respect to the excretion of urine, sodium, chloride and calcium, but the combination caused significantly less excretion of potassium (p0.05) than furosemide. After a lag-phase of 33.9±5.4 min the maximum plasma concentration of furosemide was reached after 3.47±0.66 h, and the elimination half-life was approximately 2 h. After a lag-phase of 33.0±17.8 min the maximum plasma concentration of the main metabolite of triamterene, the OH-TA sulphuric acid ester, was reached after 1.7±0.59 h, and its elimination half-life amounted to 1.25±0.37 h. Because of the sustained release of furosemide from the retard-formulation, its principal pharmacokinetic parameters were better adapted to those of triamterene. The consequences were not only a protracted effect but also an improved electrolyte profile, especially with regard to reduced loss of potassium. In the case of renal insufficiency, however, the potassium level in serum might be increased to an undesirable extent.     

Pharmacokinetic and pharmacodynamic changes of furosemide after intravenous and oral administration to rats with alloxan-induced diabetes mellitus

Because some physiological changes occurring in diabetes mellitus patients could alter the pharmacokinetics and pharmacodynamics of the drugs to treat the disease, the pharmacokinetics and pharmacodynamics of furosemide were investigated after intravenous (i.v.) and oral administration of the drug (6 mg per whole body weight) to control rats and alloxan-induced diabetes mellitus rats (AIDRs). After i.v. administration, the total body clearance (5.47 versus 7.05 mL min⁻¹ kg⁻¹) was significantly slower in AIDRs and this was due to significantly slower renal clearance (2.35 versus 4.33 mL min⁻¹ kg⁻¹) because the nonrenal clearance was comparable between two groups of rats. The 8 h urinary excretion of furosemide after i.v. administration decreased significantly (2280 versus 3760 μg) in AIDRs due to impaired kidney function; the glomerular filtration rate measured by creatinine clearance was significantly slower (2.86 versus 4.33 mL min⁻¹ kg⁻¹) and both the plasma urea nitrogen (43.5 versus 17.3 mg dL⁻¹) and kidney weight (0.953 versus 0.749% of body weight) increased significantly in AIDRs. This resulted in a significant decrease in the 8 h urine output per g kidney (17.8 versus 43.6 mL) in AIDRs. However, the 8 h diuretic efficiency was not significantly different between two groups of rats. After oral administration, the area under the plasma concentration–time curve from time 0 to 8 h decreased significantly in AIDRs (1200 versus 1910 μg·min mL⁻¹) due to considerably decreased absorption of furosemide from gastrointestinal tract of AIDRs. After oral administration, the 8 h urine output per g kidney (18.6 versus 36.4 mL) also decreased significantly in the AIDRs due to significantly decreased 8 h urinary excretion of furosemide (405 versus 2210 μg), however, the 8 h diuretic efficiency increased significantly (127 versus 35.2 mL mg⁻¹) in AIDRs. © 1998 John Wiley & Sons, Ltd.     

Comparison of the pharmacodynamic effects of furosemide and BAY g 2821 and correlation of the pharmacodynamics and pharmacokinetics of BAY g 2821 (muzolimine)

Summary In a biometrically planned, double-blind study on 12 Oedema-free male patients the saluretic effect of muzolimine 30 mg was compared with furosemide 40 mg. The plasma level of muzolimine was determined and correlated with its pharmacodynamics. In terms of excretion during the 12-hour observation period muzolimine 30 mg had as great a cumulative effect as furosemide 40 mg. There was a significant difference in the time-response curve. During the first two hours furosemide 40 mg had more saluretic effect than muzolimine 30 mg. Between two and four hours there was no significant difference between the two substances. Between four and six hours, however, muzolimine was somewhat more effective than furosemide, although the difference did not reach the level of significance. After 6 h there was no longer any difference between the two compounds. The half-life of the fall in concentration of muzolimine in plasma was 3.7 up to 10 h after its administration. The time-response curve of the increased urine excretion correlated well with the time course of the concentration of muzolimine in plasma.     

药动药效联合模型定量分析方法的研究现状

药动药效联合模型在药理学研究中正在发挥越来越重要的作用。本文介绍了近年来该领域定量计算方面的一些新概念和新进展，包括药动学和药效学模型、药动药效联合模型的四个属性、Sheiner效应室理论应用时应该注意的问题及药动药效联合模型的计算程序等。     

Pharmacokinetics and pharmacodynamics of furosemide in protein-calorie malnutrition

The influence of dietary protein deficiency on pharmacokinetics and pharmacodynamics of furosemide was investigated after iv bolus (1 mg/100 g) and oral (2 mg/100 g) administration of furosemide to male Sprague-Dawley rats fed on a 23% (control) or a 5% (protein-calorie malnutrition: PCM) protein diet ad lib.for 4 weeks. After iv administration, the mean values of CL _R , V _{ss, and the percentages of dose excreted in 8-hr urine as furosemide were increased 81, 31, and 61%, respectively, in PCM rats when compared with those in control rats, however}, CL _NR was 54% decreased in PCM rats. The decreased CL_NR in PCM rats suggested the significantly decreased nonrenal metabolism of furosemide. The urine volume per g kidney after iv administration was not significantly different between the two groups of rats although the amount of furosemide excreted in 8-hr urine per g kidney increased significantly in PCM rats. The diuretic, natriuretic, kaluretic, and chloruretic efficiencies reduced significantly in PCM rats after iv administration. After oral administration, the extent of bioavailability increased considerably from 27.6% in control rats to 47.0% in PCM rats, probably as a result of decreased gastrointestinal and hepatic first-pass metabolism. This was supported by a tissue homogenate study; the amount of furosemide remaining per g tissue after 30-min incubation of 50 g of furosemide with the 9000 × gsupernatant fraction of stomach (42.4 vs. 47.9 g) and liver (41.4 vs. 45.9 g) homogenates increased significantly in PCM rats. No significant differences in CL_R and t_1/2 were found between the control and the PCM rats after oral administration. The 24-hr urine volume and the amount of sodium excreted in 24-hr urine per g kidney increased significantly in PCM rats, and this might be due to a significantly increased amount of furosemide reaching the kidney excreted in urine per g kidney.This work was supported in part by a research grant from the Korea Science and Engineering Foundation, 1990–1992.     

Receptor-mediated pharmacokinetic/pharmacodynamic model of interferon-beta 1a in humans

Purpose. An integrated receptor-based pharmacokinetic/pharmaco- dynamic (PK/PD) model of interferon- 1a (IFN- 1a) previously developed for monkeys was used to capture the time-course of drug and induced neopterin concentrations after intravenous (IV) and subcutaneous (SC) dosing in humans. Methods. Data were extracted from the literature by digitalization. Single-dose (3 IV doses and 1 SC dose) PK/PD profiles were simultaneously fitted using the basic model and the ADAPT II computer program. Additional submodels incorporating neutralizing antibody formation and negative feedback inhibition were applied to account for drug accumulation and lower than expected neopterin concentrations encountered after multiple-dosing (1 SC dose every 48 hs). Results. The basic model jointly-captured the nonlinear PK behavior of the drug and induced neopterin concentrations after all single doses. Slow and incomplete absorption (F = 0.33) of the SC dose resulted in prolonged drug concentrations reflective of flip-flop kinetics. Despite lower drug concentrations, SC dosing produced a similar neopterin profile as compared with the IV doses; however, with a longer time to peak effect and slightly higher neopterin concentrations at later time points. The PD component of the model represents a modified precursor-dependent indirect response model driven by the amount of internalized drug-receptor complex. The latter stimulated a 6-fold increase in the production of the neopterin precursor (S_max = 5.89). Drug accumulation and lower than expected neopterin concentrations after multiple dosing were also captured after the inclusion of the submodels. Conclusions. The present integrated PK/PD model for IFN- 1a is mechanistic in nature with receptor-mediated disposition and dynamics and was successfully applied to human clinical data.