青蒿琥酯在奶牛体内的药代动力学与代谢

青蒿琥酯(artesunate,AS)是抗疟新药青蒿素的一个活性衍生物。近年来我国兽医工作者将其用于治疗牛羊泰勒氏焦虫病及双芽、巴贝斯焦虫病、鸡球虫病和耕牛血吸虫病,也收到了满意的效果。AS在大白鼠、兔、狗及人体内的药代动力学研究已见报道。本     

Tissue distribution of propafenone in the rat after intravenous administration

Tissue distribution of propafenone has been studied in the rat. Measurement of propafenone was made in several tissues: plasma, heart, kidney, lung, liver, muscle, fat and brain, after i.v. administration of 2 mg/kg of the drug. The plasma propafenone kinetics profile can be described by a two-compartmental model. The pharmacokinetic parameters, derived from plasma levels, showed a t1/2 beta of 55.4 min, the central Vd/kg of 2.4 ml/kg, the Cl of 62.8 ml/min.kg and the AUC0-oo of 31.6 micrograms.min/ml. The analysis of the propafenone tissue distribution showed the highest concentration of drug in the lung, followed by the heart and kidneys. A significant concentration was found in brain, muscle and adipose tissue, with concentration ratios (tissue/plasma) above 1. The half-life values obtained for individual organs and tissues are similar to those obtained in plasma, around 1 h. In the post-distributive phase, plasma and tissue concentrations decline in parallel.     

Penetration of cefbuperazone, a new cephamycin antibiotic, into human peritoneal exudate

Pharmacokinetic studies were carried out on cefbuperazone ( CBPZ ) in 9 patients undergoing postoperative drainage. The concentration of CBPZ in serum and peritoneal exudate after one shot intravenous administration of 1 g was measured by bioassay and calculated respectively by two- and one-compartment open model. The results obtained were as follows: The pharmacokinetic parameters calculated from the serum levels were compared to those reported previously; T1/2 = 101 min., Vd = 4.06 L and Cl = 76 ml/min. The simulation curve of the peritoneal exudate level fit fairly with the mean values of 6 patients. It appeared that CBPZ penetrated somewhat slowly into peritoneal exudate with the peak value of 27.05 micrograms/ml at about 1 hour after the administration. The exudate levels thereafter declined more slowly than the serum ones (T1/2 = 134 min.). IT was 6.2 micrograms/ml even at 6 hours after the administration.     

盐酸放线瑞香宁的紫外二阶导数光谱法测定及在兔体内的药代动力学

盐酸放线瑞香宁(actinodaphine-HCl)系从莲叶桐科青藤属植物黑吹风(Illigera khasiana C.B Clarke)中分离提取而得的有效成分,结构式如图1。药理试验证明有解热、镇痛、解痉等作用。本文报告用紫外二阶导数光谱法研究盐酸放线瑞香宁在兔体内的药代动力学结果。家兔4只,体重2.8±0.6kg。盐酸放线瑞香宁由本所植化室提供。氯仿、乙醇均为A.R。Perkin-Elmer型紫外—可见光分光光度计系美国产品。     

The pharmacokinetic studies on astromicin in rats. Intramuscular, intravenous or drip intravenous administration

Absorption, tissue distribution and excretion of astromicin (ASTM) were studied in rats after intramuscular (i.m.), intravenous (i.v.) or drip intravenous (d.i.v.; for 15, 30 min. or 60 min.) administration at a dose of 20 mg/kg. The pharmacokinetic studies of ASTM were carried out using one-compartment open model (i.m.) or two-compartment open model (i.v. and d.i.v.). The peak values of ASTM observed in serum were 48.6 micrograms/ml (i.m.), 255.3 micrograms/ml (i.v.), 57.5 micrograms/ml (15 min. d.i.v.), 45.9 micrograms/ml (30 min. d.i.v.) and 39.1 micrograms/ml (60 min. d.i.v.). The pharmacokinetic parameters of ASTM after 15 min. d.i.v. administration were calculated as follows: Kel 0.110 min-1, T1/2 21.4 min., Vd beta 0.310 L/kg, Tmax 15.0 min., Cmax 58.6 micrograms/ml, AUC 1,991 micrograms X min/ml. ASTM was rapidly distributed into the kidneys and lungs. The peak values of ASTM in the kidneys were 156.8 micrograms/g (i.m.), 185.2 micrograms/g (i.v.), 132.9 micrograms/g (15 min. d.i.v.), 135.3 micrograms/g (30 min. d.i.v.) and 117.3 micrograms/g (60 min. d.i.v.). Urinary recovery rates of ASTM amounted to 85.5% (i.m.), 99.5% (i.v.) or 87.9% (30 min. d.i.v.). After i.m. or 30 min. d.i.v. administration of ASTM, no active metabolite was found in urine of rats.     

蛇床子素在兔体内药物代谢动力学

目的研究蛇床子素在兔体内的药物代谢动力学。方法用高效液相色谱法,以丹皮酚为内标,以甲醇-水(80∶20)为流动相,测定兔血液中蛇床子素(iv,10 mg·kg^-1)的含量。采用3P87程序计算药物代谢动力学参数。结果蛇床子素iv药代动力学符合二房室开放模型,T_1/2α=5.81 min,T_1/2β=42.2 min,K21=0.036 0·min^-1,K₁₂=0.045 0·min^-1,K₁₀=0.054 0·min^-1,AUC=235 mg·min·L^-1,CLs=0.043 0 L·min^-1·kg^-1,V_C=0.780 L·kg^-1。结论蛇床子素在兔体内分布及消除较快     

Pharmacokinetics of pipecurium bromide, a new non-depolarizing neuromuscular blocking agent, in humans

The pharmacokinetics of 2 beta, 16 beta-bis-(4'-dimethyl-1'-piperazino)-3 alpha, 17 beta-diacetoxy-5 alpha-androstane dibromide (pipecurium bromide, Arduan), a new non-depolarizing neuromuscular blocking agent, was studied in surgical patients. Plasma concentration-time curves of pipecurium bromide were evaluated by fitting the data to a bi-exponential equation. The average half-lives were T 1/2 alpha = 4.1 +/- 1.4 (n = 8) and T 1/2 beta = 44 +/- 7 (n = 8) min. The pharmacokinetic parameters of pipecurium bromide were found as follows: apparent distribution volume V beta = 261 +/- 28 (n = 8) ml/kg, plasma clearance Cl = 320 +/- 55 (n = 8) ml/min. The microconstants of two-compartment open models were also calculated.     

小儿热感宁注射液在兔体内的药代动力学研究

目的 :研究小儿热感宁注射液在家兔体内的药代动力学特征。方法 :采用高效液相色谱法测定小儿热感宁注射液中主要成分葛根素在兔血浆中的浓度 ,用3p87程序计算药代动力学参数。结果 :小儿热感宁注射液在兔体内的药代动力学过程符合开放二室模型 ,主要药代动力学参数为T1/2α=5 25min ,T1/2β=36 04min ,K10=0 042min ,K12=0 063min ,K21=0 093min ,AUC=2561 49μg/(ml·min) ,CL=4 6ml/(min·kg)。结论 :该研究可为小儿热感宁注射液的临床应用提供一定科学依据     

Disposition of N-methyl-[ring-3,5-3H]tyramine in rabbits and mice

After iv bolus injection of N-methyl-[ring-3,5-3H] tyramine ([3H]MT) 14.8 MBq/kg in rabbits, the plasma concentration-time data was found to be in accordance with the 2-compartment model. The pharmacokinetic parameters were: T1/2 alpha = 0.3 min, T1/2 beta = 5.6 min, K12 = 0.69/min, K21 = 0.21/min, K10 = 1.6/min, VC = 0.4 L/kg, Cl = 0.62 L/kg.min-1. [3H]MT was taken up by organs rapidly and extensively. Two min after administration, a large amount of radioactivity was detected in every organ sampled. The highest amounts were in the kidney and liver, followed by lung, small intestine, heart, skeletal muscle, spleen, brain and fat. The drug was metabolized extremely fast in vivo. The metabolites were found in the plasma chromatogram just 0.5 min after dosing, while over 80% were found in the urine within 1 h. After a 1 h collecting period, the radioactivity recovered in the urine amounted to 79% of the injected dose. By the end of a 6 h collection, almost no drug was detected in the body.     

The pharmacokinetics of 125I-atrial natriuretic factor in anaesthetized rats. Effects of neutral endopeptidase inhibition with candoxatrilat and of ANF-C receptor blockade.

The effects of candoxatrilat (cis-4-([2-carboxy-3-(2-methoxyethoxy)propyl]-1-cyclopentanecarbonyla mino)- 1-cyclohexane carboxylic acid) and the ring-deleted atrial natriuretic factor (ANF) analogue C-ANF4-23 (des[Gln18, Ser19, Gly20, Leu21, Gly22]ANF4-23-NH2) on the clearance of (3-[125I]iodotyrosyl28)ANF (125I-ANF) were studied in both intact and nephrectomized anaesthetized rats. HPLC analysis was used to verify that the 125I-labelled material isolated by solid phase extraction of rat plasma was intact ANF. In intact animals, clearance of 125I-ANF was biphasic with a T1/2 alpha of 17 sec and T1/2 beta of 95 sec. Volume of distribution (Vd) was 564 mL/kg and plasma clearance (Clp) 248 mL/min/kg. Candoxatrilat, over the dose range 0.01-10 mg/kg i.v., increased T1/2 beta (by a maximum of 56%) and decreased Clp (by up to 52%) with no effect on T1/2 alpha or Vd. C-ANF4-23 (10 micrograms/kg+1 microgram/kg/min i.v.) reduced Vd (by 57%) and Clp (by 54%) with no effect on T1/2 beta, whilst abolishing the T1/2 alpha phase in over 50% of animals. Increasing the dose of C-ANF4-23 did not increase the effect on any of these parameters, apart from a small increase in T1/2 beta. Combining the two agents resulted in a substantial decrease in Clp (76%) whilst the reduction in Vd and increase in T1/2 beta were comparable to those seen with C-ANF4-23 and candoxatrilat alone, respectively. In nephrectomized rats, the pharmacokinetics of 125I-ANF and the changes induced by candoxatrilat were similar to those observed in intact animals, whilst the effects of C-ANF4-23 alone were greater than in intact animals. The combination of C-ANF4-23 and candoxatrilat again produced a substantial increase in T1/2 beta (153%) and decreases in Vd (55%) and Clp (78%) in nephrectomized animals, although these changes could not be distinguished from those seen in intact animals treated with the same combination. Our studies indicate that neutral endopeptidase and ANF-C receptors are both major, and approximately equal, clearance mechanisms for 125I-ANF, together accounting for at least 75% of the total clearance of this peptide in the rat.     

间硝苯地平在兔体内的药物动力学

目的：研究间硝苯地平剂量效应的药代动力学。方法：兔被随机分成３组,分别静脉注射高、中、低（０５,１,２ｍｇ／ｋｇ）３种剂量的间硝苯地平,用ＨＰＬＣ法测定血浆药物浓度。结果：间硝苯地平的血药浓度和时间数据经拟合均符合二室模型,主要药动学参数如下（以剂量１ｍｇ／ｋｇ为例）：Ｖｄ＝０３７Ｌ／ｋｇ,Ｔα／２＝６４ｍｉｎ,Ｔβ／２＝８４１ｍｉｎ,ＡＵＣ＝９４１ｍｇ·ｍｉｎ／Ｌ,ＣＬ＝０６５Ｌ／（ｋｇ·ｈ）。各剂量组间的ＣＬ,Ｔβ／２经方差分析无显著差异,用单位体重的曲线下面积对剂量进行线性回归存在显著正相关。结论：间硝苯地平分布广,消除也迅速;在剂量０５～２ｍｇ／ｋｇ范围内消除动力学呈非剂量依赖性关系。     

Pharmacokinetics of 2-methoxyphenylmetyrapone and 2-bromophenylmetyrapone in rats.

The pharmacokinetics of two 2-substituted phenylmetyrapone analogues, 2-methoxyphenylmetyrapone (2-MPMP) and 2-bromophenylmetyrapone (2-BrPMP), developed as potential adrenal imaging agents, were investigated in conscious male rats following an intravenous dose of 25 mg/kg. Arterial blood samples (0.25 ml) were collected at various intervals for up to 7 h after dose and subjected to reversed-phase HPLC analysis. Blood concentrations versus time profile for each compound was determined and the pharmacokinetic parameters calculated using the model-independent approach. Blood concentrations of 2-MPMP declined biexponentially with mean initial (t1/2alpha) and terminal (t1/2beta) half-lives of 3.6 and 23.1 min, respectively. The corresponding area under the curve (AUC(0-infinity)) was 159.3 microg x min/ml, the total blood clearance (CI) was 158.3 ml/min and the volume of distribution (Vd) was 5.2 l. Two metabolites of 2-MPMP, namely 2-hydroxyphenylmetyrapone (2-OHPMP) and 2-methoxyphenylmetyrapone N-oxide (2-MPMP-NO), were detected in the blood and their elimination from blood was almost parallel to that of the parent compound. The maximum blood concentrations (Cmax) of 2-OHPMP and 2-MPMP-NO were approximately 0.9 and 1.7 microg/ml, respectively. Blood concentrations of 2-BrPMP declined monoexponentially with a mean t1/2beta of 12.0 min. The pharmacokinetic parameters for 2-BrPMP were: AUC(0-infinity), 193.7 microg x min/ml; Cl, 131.7 ml/min and Vd, 2.3 l. 2-Bromophenylmetyrapone N-oxide was the only one metabolite detected in the blood, its Cmax and AUC0-infinity were 10.1 microg/ml and 1690.0 microg x min/ml, respectively.     

肝肾功能损害状态下蝙蝠葛碱的药动学

以HgCl_2所致家兔急性中毒性肾功衰(ARF)和CCl_4所致急性中毒性肝损害(ALI)为模型,研究蝙蝠葛碱(Dau)在肝肾功能损害状态下的药代动力学。结果表明:ARF组的药代动力学参数与正常对照组无显著性差异。ALI组α,t1/2α,V_d,V_c与正常对照组无显著差异,其β,K_(10),Cl值均显著低于正常对照组,其t1/2β值显著高于正常对照组。     

稳定同位素结合GC-MS法测定大鼠体内川芎哚的药物动力学参数(英文)

目的:测定川芎哚(川芎Ⅲ号碱,perlolyrine)的药动学参数。方法:以[2-~(15)N]川芎哚为内标准及GC-MS的SIM(选择性离子监测)为检测手段,定量测定大鼠体内川芎哚的含量及其药代动力学参数。结果:大鼠灌胃给予川芎哚2mg·kg~(-1)后,川芎哚在大鼠体内呈二室模型分布,其药代动力学参数为:T_((1/2)α)=0.33h,T_((1/2)β)=4.52h,T_(1/2)(ka)=0.14h,T_(max)=0.35h,C_(max)=18.84μg/L,K_(12)=0.88h~(-1),K_(21)=0.42h~(-1),K_(10)=0.32h~(-1),V/F=109.22 L·kg~(-1),AUC=112.68μg·h·L~(-1)。结论:本法灵敏度高、特异性强且准确性好,为测定川草哚药代动力学参数提供了实用的分析方法。本研究为川芎哚临床应用提供了重要的参考资料。     

Cimetidine pharmacokinetics

The pharmacokinetics of cimetidine was studied in 9 patients at a single intravenous (200 mg) and oral (400 mg) administration. The pharmacokinetic parameters at intravenous administration were calculated according to a two-compartment model. The time-concentration curve after oral drug administration had two maxima between 45 min and 2 hrs with approximately equal concentrations of cimetidine. The main pharmacokinetic parameters of cimetidine were calculated as follows: t1/2 beta = 1.7 h, t1/2 alpha = 0.12 h, Vd = 1.0 1/kg, Cis = 0.43 1/kg/h, Cior = 1.2 1/kg/h, bioavailability 36%. At the course treatment (1 g per day) cimetidine concentration before the morning dose on the 6th and 12th days remains at the same level.     

Pharmacokinetics of intravenous propafenone in patients with episodes of paroxysmal supraventricular tachycardia

The plasma concentration time curves of propafenone after administration of single i.v. (2.3 +/- 0.2 mg/kg) doses have been studied in ten patients undergoing an electrophysiological study to evaluate episodes of recurrent supraventricular tachycardia. The propafenone kinetics profile can be described by a two-compartment open model. Mean values of main variables were t 1/2 alpha = 2.8 min, t 1/2 beta = 80 min, Kel = 0.12 min, -1, Vd beta = 1.6 1/kg, Cl = 1.03 1/h and AUR = 3.1 mg/h-1.     

Vancomycin pharmacokinetics and Bayesian estimation in pediatric patients

The vancomycin pharmacokinetic profile was characterized in six pediatric patients and the potential of nonlinear mixed effects modeling and Bayesian forecasting for vancomycin monitoring was explored using NONMEM V (1.1). Based on steady state serial vancomycin concentrations, the estimates of mean t1/2, Vd, and Cl derived by the Sawchuk and Zaske method (1) were 3.52 hours, 0.57 L/kg, and 0.12 L/h per kg, respectively. NONMEM analysis demonstrated that a weight-adjusted two-compartment model described individual patients' data better than a comparable one-compartment model. The two-compartment estimates of mean t1/2alpha, t1/2beta, Vss, and Cl were 0.80 hour, 5.63 hours, 0.63 L/kg, and 0.11 L/h per kg, respectively. The relatively long mean t1/2alpha suggests that peak vancomycin concentrations measured earlier than 4 hours postdose do not reflect postdistributional serum concentrations. NONMEM population modeling revealed that a weight-adjusted two-compartment model provided a better fit than a comparable one-compartment model. The resulting population parameters and variances were fixed in NONMEM to obtain Bayesian predictions of individual vancomycin serum concentrations. Bayesian estimation with either a single midinterval or trough sample has the potential to provide accurate and precise predictions of vancomycin concentrations. This should be evaluated using a vancomycin population pharmacokinetic model based on a larger sample of pediatric patients.     

乙醇对苯妥英钠药代动力学的影响

目的 :观察乙醇对苯妥英钠药代动力学的影响。方法 :分别对8只家兔单用苯妥英钠和乙醇合用后苯妥英钠的药代动力学参数变化进行研究和比较 ,采用紫外分光光度法测定苯妥英钠的经 -时血药浓度 ,以“3p87”程序拟合药代动力学参数。结果 :合用乙醇后 ,苯妥英钠的AUC由 (4108 64±1039 98)ml/(L·min)降至 (1903 65±1003 40)mg/(L·min) ;T1/2(ke)由 (98 45±26 4)min降至 (82 84±25 5)min ;Vd 由 (0 3475±0 0360)L/kg升至 (0 6819±0 1901)L/kg ;CLs 由 (0 0026±0 0008)ml/(kg·min)升至(0 0062±0 0022)ml/(kg·min) ;Cmax 由 (29 0±2 94)mg/L降至 (16 0±5 9)mg/L。结论 :合用乙醇后 ,苯妥英钠的消除在体内明显加快