芍药甙在兔和大鼠体内的药动学研究

兔iv25mg·kg~(-1)芍药甙后,血药浓度—时间曲线符合二室模型。药动学参数为T_(1/2α)=5.93min,T_(1/2β)66.02min,V(?)=516.8ml·kg~(-1),CL=6.11ml·kg~(-1)·min~(-1)。兔ig250mg·kg~(-1)芍药甙,生物利用度为F=7.24％±4.15％,T_(max)=77.4min,C_(max)=21.57mg·L~(-1)大鼠ig550mg·kg~(-1)芍药甙,24h内粪、尿排泄量及iv55mg·kg~(-1)7h内胆汁排泄量分别占给药量的10.61％、1.08％、864％。离体肝脏灌流结果提示:芍药甙在肝内代谢少.     

正常人静滴甲硝唑的药代动力学研究

本文以高效液相色谱法对8名健康受试者进行了体内甲硝唑药代动力学初步研究。静脉滴注后的药—时曲线符合开放型双室模型,t_(1/2)α与t_(1/2)β值分别为1.686±1.517与11.995±2.605h;k_(10)、k_(12)及k_(21)分别为0.097±0.056h~(-1)、0.609±0.817h~(-1)及0.748±0.701h~(-1);V_1及V_2分别为0.6±0.2及0.231±0.142L/kg。     

清胰Ⅱ号颗粒在大鼠体内药动学研究

目的:研究大鼠ig给予清胰Ⅱ号颗粒,其有效成分大黄素在大鼠体内的药动学过程。方法:大鼠分别ig给予不同剂量(2.5、5.0 g·kg~(-1))的清胰Ⅱ号颗粒,采用高效液相色谱法在不同时间点测定血浆中大黄素浓度,并计算药动学参数。结果:给予不同剂量药物的大鼠血浆中大黄素的t_(1/2α)分别为(9.468±8.46)、(21.68±17.867)h;t_(1/2β)分别为(15.388±5.46)、(39.63±24.39)h;t_(max)分别为(2.500±3.479)、(5.333±3.266)h;C_(max)分别为(0.058±0.004)、(0.101±0.007)mg·L~(-1);CL分别为(33.027±9.365)、(9.405±5.846)L·h~(-1)·kg~(-1);AUC(0-∞)分别为(0.652±0.201)、(1.364±0.267)mg·h~(-1)·L~(-1),其动力学过程符合二室模型。结论:建立了大鼠血浆中大黄素浓度检测方法,得到了相关药动学参数,可为清胰Ⅱ号颗粒后续药动学-药效学研究奠定理论基础。     

新抗病毒抗生素17997在大鼠体内药代动力学和组织分布研究

目的:建立大鼠血浆、胆汁和组织中17997的高效液相色谱测定法,研究大鼠静脉注射17997后药代动力学、组织分布和胆汁排泄,以及血浆蛋白结合率。方法:SD大鼠以 4或1 mg·kg~(-1)剂量尾静脉注射给药,按实验设计采集血样、组织、胆汁,用HPLC法测定药物浓度;血浆蛋白结合率用平衡透析法测定。结果:17997保留时间为约7.0min;大鼠静脉推注4mg·kg~(-1)17997后药代动力学参数如下:消除半衰期为75.71 min,C_0为4.51μg·mL~(-1),清除率为52.5mL·min~(-1)·kg~(-1),药时曲线下面积AUC为76.16 min·μg·mL~(-1);给药后15 min 17997在大鼠体内组织分布依次为肺16.55 μg·g~(-1)、十二指肠7.34 μg·g~(-1)、肝6.51 μg·g~(-1)、心4.18 μg·g~(-1)、肾3.31 μg·g~(-1)、脾3.12 μg·g~(-1)、胸腺1.83 μg·g~(-1)和淋巴结0.74 μg·g~(-1)。大鼠静脉推注4、1mg·kg~(-1)17997后24 h胆汁排泄率分别为(55.4±9.4)％和(58.8±11.8)％;大鼠血浆蛋白结合率为(92.27±2.91)％。结论:本实验建立了测定大鼠血浆、胆汁和组织中17997的高效液相色谱紫外检测法,操作便捷,高效灵敏,样品用量少。大鼠静脉推注17997后体内分布排泄速度较快,肺组织浓度最高,蛋白结合率高,主要通过胆汁排泄。应用于临床时,需综合考虑各种因素对     

盐酸阿芬太尼在手术病人中的药代动力学研究

本文进行了两组不同剂量的阿芬太尼在14例手术病人中药代动力学研究。7例一次性iv 80μg·kg~(-1)阿芬太尼,另7例一次性iv 40μg·kg~(-1)。用RIA方法测定0-8 h阿芬太尼的血浆浓度和0-48 h尿中的回收率。研究表明:阿芬太尼在两组病人体内的药代动力学过程均为3室模型。阿芬太尼的初级消除很快,给药后30 min内90％的原型药被消除。病人血浆浓度未发现2次上升现象。二者药-时曲线接近平行,说明阿芬太尼的代谢过程为1级消除。两组阿芬太尼的药代动力学数据经t检验无显著差异(P>0.05)。阿芬太尼的快、慢分布相和消除相的半衰期t_(1/2)π,t_(1/2)α和t_(1/2)β分别为0.71 min±s 0.37 min,11.66 min±s 3.46 min和86.12 min±s 19.15 min;平均总体和中心室的分布容积Vd、Vc分别为34.22L±s 8.27L和4.23L±s 1.72L;平均总体清除率Cl为0.29 L·min~(-1)±s 0.08L·min~(-1)。另外,k_(12)/k_(21)为1.5,k_(13)/k_(31)为3.5,k_(10)大于k_(31)。用药后48 h以内,40μg·kg~(-1)组和80μg·kg~(-1)组的病人尿中排出的原形阿芬太尼分别占总给药量的0.68％±s 0.72％和0.66％±s 0.54％。其肾清除率分别为0.0016 L·min~(-1)±s 0.0011 L·min~(-1)和0.0021 L·min~(-1)±s 0.0015 L·min~(-1)。     

芪嘧啶的药代动力学

本文报告芪嘧啶在大鼠(150 mg/kg)和家兔(100mg/kg)一次ig的药代动力学研究结果。采用分光光度法测定生物样品中的药物浓度,用3P87实用药代动力学程序处理药物浓度数据,并自动算出各项动力学参数和C-T曲线图。主要参数t_(1/2ke),t_(peak),C_(max),CL和V_d在大鼠分别为6.55 h,1.32 h,9.5μg/ml,1.46 L·kg~1·h~1和13.8 L/kg,家兔分别为1.98h,1.00h,7.1μg/ml,4.09L·kg~1·h~(-1)和11.7 L/kg。结果表明药物在大鼠肝中达峰时间短,峰浓度高,清除较慢,在肝、肾含量高于其它组织。由尿粪排泄量小,72 h累计量仅为给药量的11.5％,而且排泄速度慢,一次给药后72 h仍有一定量药物由粪尿排泄。     

国产米利酮的药动学试验

本文报道用高效液相色谱法对家兔口服(p·o)和静注(i·v)milrinone(M)后的药动学试验。ivM(5mg/kg)后的数据宜用三室模型拟合,消除半衰期(t1/2)为42.0±7.8min,分布容积(Vc)为0.233±0.03L·kg~(-1),药-时曲线下面积(AUC_0~∞为5.58±1.96μg·kg~(-1)·h;p·oM(10mg/kg)液剂的t1/2为2.06±0.57h,AUC_0~∞为5.59±1.16μg·kg~(-1)·h,峰药浓度(C_(max))为2.12±0.6μg/ml,达峰时间(t_(max))为0.8±0.41h。     

蒿甲醚在兔体内的药代动力学

本文报道蒿甲醚在兔体内的药代动力学。静脉输注蒿甲醚脂肪乳剂(蒿甲醚80mg/kg)后,血药时间数据用NONLIN程序拟合曲线,符合线性二室开模型。药代动力学参数的平均(SD)为:t1/2(α和β)分别为0.144(0.077)h和0.896(0.371)h;k_(2t),k_(10)和k_(12)分别为1.235(0.705),4.143(1.370)和1.140(0.951)h~(-1);V_c,V_d(area)和V_(d(ss))分别为0.609(0.119),2.985(0.787)和1.054(0.202)L/kg;清除率为2.401(0.339)L·kg~(-1)·h。 肌内注射油剂250mg/kg或125mg/kg,血药时间数据按矩量法计算,得吸收速率常数(Ka)为0.0377(0.0119)h~(-1);吸收程度为36.14(18.39)％。     

槲皮素在兔体内的药代动力学

槲皮素为黄酮类化合物。兔iv槲皮素10m g·kg~(-1)后.血药浓度—时间曲线符合二室模型。T_(1/2)(α)为2.91 ±1.36min,T_(1/2)(β)183.78±82.67min,V_B为0.624±0.225 L·kg~(-1),CL为3.15±2.11 ml·kg~(-1)·min~(-1).槲皮素10mg·kg~(-1)ig后,生物利用度为42.7％,药峰浓度(C_(Dk))为10.9mg·L~(-1),药峰时间(t_(pk))为60min。iv槲皮素后.药物以原型和代谢产物两种形式经尿、胆汁排泄,消除较迅速。     

盐酸小檗碱在Beagle狗静脉注射和口服药动学研究

传统观念认为小檗碱口服吸收差,而近年来,临床口服小檗碱用来治疗心律失常及充血性心衰.为解决其中的矛盾,本实验建立了HPLC方法(最低检测限为2μg·L~(-1))研究Beagle狗po和iv小檗碱的药代动力学、100 mg静脉注射的药—时曲线符合二室模型,K.为10.18 h~(-1),T_(1/2u)为0·15·h~(-1)T_1/2β为12.59·h~(-1),CL为60.70 L·h~(-1),AUC达1979.31 μg·L~(-1)V_d为699.53L。280 mg·kg~(-1)组发生呕吐·仅一狗可计算P—K参数,T_(max)为3.71h,C_(max)为15.46 μg·L~(-1),AUC为777.29μg·h~(-1)·L~(-1).T T_(1/za)0.63 h·T_(1/z)el34.82h,V_a为125.41L,K.为0.02·h~(-1),CL为2.64 L·h~(-1),45 mg·kg~(-1)一次口服以及45 mg·kg~(-1)Bid连续给药1wk的血药浓度都在10μg·L~(-1)以下。700 mg·kg~(-1)组因发生严重呕吐.腹泻,药物吸收差.血浓度在10 μg·L~(-1)以下,不能计算P—K参数.     

黄芪甲苷在兔体内的药动学和在大鼠的排泄(英文)

目的 :研究黄芪甲苷在家兔体内的药动学和在大鼠的排泄。方法 :健康家兔和大鼠一次静脉注射 (静注 )给予黄芪甲苷 4mg·kg- 1,高效液相色谱 蒸发光散射检测器法检测兔血浆和大鼠尿及粪黄芪甲苷浓度 ,用 3P97药动学软件对兔血浆浓度 时间数据进行动力学分析和计算药动学参数 ,并估算大鼠体内的排泄情况。结果 :黄芪甲苷静注给药后 ,T12 α 为 0 .10h ,T12 β 为 1.4h ,Vc 为 0 .15L·kg- 1,VD 为 0 .6L·kg- 1,Cl为 0 .32L·h- 1·kg- 1,AUC为 15mg·L- 1·h。大鼠静注给药后 ,原形从尿和粪排出量分别为给药量的 16 %和 3.2 %。结论 :家兔体内黄芪甲苷的动力学过程符合二室模型 ,大鼠仅有少量原形药物从尿和粪排泄。     

Alpha 1b-adrenoceptors mediate renal tubular sodium and water reabsorption in the rat.

1. It is known that activation of alpha 1-adrenoceptors causes renal vasoconstriction and increased tubular Na+ and water reabsorption, with the alpha 1a-subtype mediating the constrictor effect. 2. This study examines which subtype of alpha 1-adrenoceptors mediates tubular Na+ and water reabsorption in pentobarbitone-anaesthetized rats. In order to avoid systemic effects, phenylephrine (0.3 to 30 micrograms kg-1), methoxamine (0.1-10 micrograms kg-1) and vehicle were infused into the right renal artery (via the suprarenal artery) of three groups of rats. Two other groups of rats were continuously infused with the irreversible selective alpha 1b-adrenoceptor antagonist, chloroethylclonidine (3 mg kg-1 h-1) for 1 h, prior to the construction of dose-response curves to phenylephrine or methoxamine. Another group was continuously infused with the irreversible selective alpha 1a-adrenoceptor antagonist, SZL-49 (10 micrograms kg-1 h-1) for 1 h, prior to the construction of dose-response curves to phenylephrine. Mean arterial pressure (MAP), heart rate (HR), urine flow, Na+ and K+ excretion, and urine osmolality were monitored. 3. Phenylephrine and methoxamine did not affect MAP or HR but dose-dependently and significantly decreased urine flow, urine osmolality as well as Na+ excretion and, slightly increased K+ excretion, although this was significant only for phenylephrine. 4. The antidiuretic, antinatriuretic and kaliuretic effects of phenylephrine were abolished by pretreatment with chloroethylclonidine, but were not inhibited by SZL-49. The inhibitory effects of methoxamine on urine flow and Na+ excretion were also almost totally abolished by chloroethylclonidine. 5. Our results show that alpha 1b-adrenoceptors mediate renal tubular Na+ and water reabsorption.     

The disposition and pharmacokinetics of alpidem, a new anxiolytic, in the rat.

The autoradiographic distribution, disposition, biliary excretion, and pharmacokinetics of alpidem in Sprague-Dawley rats were evaluated after iv or oral administration. Following i.v. administration, autoradiography showed that radioactivity was preferentially localized in lipid-rich tissues including central nervous system structures. After a 3-mg.kg-1 i.v. or oral dose of [14C]alpidem, more than 80% of the radioactivity were excreted in the feces over a 6-day period. Biliary excretion of radioactivity in vigile rats, about 74% of the dose over a 7-hr period after either iv or oral administration, showed that alpidem was well absorbed. The absolute bioavailability (13%) data indicated a high first-pass effect. Plasma pharmacokinetic parameters of alpidem were as follows: Vd = 5 liter.kg-1, Cl = 2.2 liter.h-1.kg-1, and terminal t 1/2 beta = 1.2-1.7 hr. Three metabolites with a pharmacological activity similar to that of alpidem were detected in plasma. They were eliminated from the central compartment with half-lives comparable to that of the parent drug. Alpidem crossed the blood-brain barrier following either i.v. or oral administration, resulting in cerebral levels 2.5 to 4 times greater than the plasma levels. Alpidem was eliminated from the central nervous system according a biphasic process with a t 1/2 alpha comparable in plasma and brain. Alpidem represented 94 and 63% of cerebral radioactivity 5 min after i.v. and oral administration, respectively. Two out of the three active plasma metabolites were detected in the brain.     

多索茶碱在大鼠体内的药代动力学

为全面了解多索茶碱在大鼠体内代谢情况,用高效薄层色谱法和光密度扫描法,给大鼠ig多索茶碱后,测定在不同时间各组织和体液中多索茶碱的含量。结果表明,多索茶碱在大鼠体内药代动力学为一室模型并能在体内迅速转化为其它代谢产物。T_1/2(Ke)为1.17～3.75h,达峰时间T(peak)为0.72～1.46h,Cmax,AUC及CL/F呈剂量依赖关系。给药1h,以胃壁浓度最高,8h除胃肠组织浓度降低较慢外,其它组织中药物浓度明显降低。尿、粪及胆汁中原形药总排出量占给药量的5.2%。血浆蛋白结合率约25%。提示多索茶碱在体内可能转化为其它代谢产物。     

A study of the action of amlodipine on adrenergically regulated sodium handling by the kidney in normotensive and hypertensive rats.

1. An investigation was undertaken to examine the effect of calcium channel blockade, induced by amlodipine, on the ability of the renal sympathetic nerves to cause an antidiuresis and anti-natriuresis in normotensive Sprague Dawley and spontaneously hypertensive rats anaesthetized with pentobarbitone. 2. Low frequency renal nerve stimulation in normotensive rats, which did not change renal blood flow, caused a 15% reduction in glomerular filtration rate and was associated with falls in urine flow of 37%, absolute sodium excretion of 47%, and fractional sodium excretion of 38%. The magnitude of these renal excretory changes was unaffected by prior administration of amlodipine at either 200 micrograms kg-1 plus 50 micrograms kg-1 h-1 or 400 micrograms kg-1 plus 100 micrograms kg-1 h-1. Amlodipine given in the higher dose, decreased basal levels of blood pressure and increased basal urine flow and sodium excretion. 3. In spontaneously hypertensive rats, renal nerve stimulation minimally affected renal haemodynamics but decreased urine flow, absolute and fractional sodium excretion by 29%, 31% and 24%, respectively. 4. Similar renal nerve stimulation in spontaneously hypertensive rats given amlodipine at 200 micrograms kg-1 plus 50 micrograms kg-1 h-1 or 400 micrograms kg-1 plus 100 micrograms kg-1 h-1 caused minimal changes in renal haemodynamics and in the excretion of water and sodium. The higher dose of drug resulted in decreased blood pressure and increased basal rates of urine flow and sodium excretion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Investigation of mezlocillin disposition with a porcine model

The suitability of the pig as an animal model for mezlocillin disposition was assessed. Serum, urine, and bile were collected after the administration of 50, 100 and 200 mg kg-1 mezlocillin to pigs and drug pharmacokinetics were characterized. Mezlocillin concentrations in biological fluids were determined by HPLC and free mezlocillin was determined by ultrafiltration. The pharmacokinetics of mezlocillin appeared to be independent of dose over the dosage range studied. Total clearance, renal clearance, and biliary clearance were 0.18 (0.05) 1 h-1 kg-1, 0.13 (0.03) 1 h-1 kg-1, and 0.07 (0.02) 1 h-1 kg-1, respectively. The steady-state volume of distribution was 0.29 (0.08) 1 kg-1. The pharmacokinetic parameters determined in the porcine model are similar to those reported for health human volunteers. Therefore, this model appears suitable for the study of mezlocillin disposition, and may be applied to the study of other agents that are appreciably biliary excreted.     

Distribution and excretion of N-Ilel Thr2-63-desulfatohirudin in rats

Objective To investigate distribution and excretion of N-Ile1Thr2-63-desulfatohirudin (rH) a recombinant hirudin newly developed in China, in rats for its development as a novel anticoagulant agent. Methods ELISA was used to determine the rH concentration in related tissues and body fluids. Tissues were collected at 15, 60 and 180min respectively, after iv administration of rH 1.0 mg·kg-1 to 3 groups of 5 rats, and homogenized. Urine, bile and feces were collected at pre-selected intervals of time after iv dosing 1.0 mg·kg-1 to 3 groups of 5 rats and assayed. Results rH following iv dosing was distributed rapidly, the rH levels in all tissues being found to be the highest at 15 min post-injection, afterwards gradually reduced. The highest concentration of rH was found in blood, the next in lung and heart, the lowest in brain. With 15 min post dose as an example, the rH contents in tissues were ranked in order of plasmalungheart adipose skeletal muscles kidney liver spleen brain. The 12 h-cumulative excretion amount of rH in urine and feces accounted for 0.03% and 0.001% of administered dose, respectively; the 6 h-cumulative excretion amount in bile was 0.02 % of the dose. Conclusions The rH is distributed mainly in blood circulation system with very low content in other tissues. The drug is excreted from urine, feces and bile of rats in extremely minute amount(only 0.051% dose), suggesting that rH undergoes extensive metabolic elimination in rat body.     

Disposition and tissue distribution of angiopeptin in the rat.

The disposition and tissue distribution of angiopeptin, a long-acting octapeptide analogue of somatostatin, were studied in rats following single iv and sc administration of the drug. Similar plasma levels and excretion values of angiopeptin were observed by using radioimmunoassay and radiolabeling techniques. Angiopeptin was absorbed fairly rapidly, with a mean peak plasma level of 25 +/- 4.1 ng/ml at 10-15 min after administration. The kinetics of angiopeptin following sc administration closely resembled those following iv administration due to rapid absorption. The pharmacokinetics of angiopeptin can be described by a two-compartment model. The plasma half-life of the drug ranged from 2.6-2.9 hr when administered sc and 1.98-2.5 hr when given iv. Distribution of angiopeptin was rapid, with the highest concentration appearing in the liver. Half-lives in the liver and bile were short. Most of the drug was excreted in the feces via the bile, while approximately 10% was excreted in the urine. Angiopeptin was also found to be secreted in the saliva. TLC and HPLC of blood, urine, feces, and bile samples did not reveal the presence of any metabolites. In conclusion, the in vivo fate of angiopeptin is characterized by little or no hepatic metabolism and rapid biliary excretion.     

Biotransformation and mass balance of faldaprevir,a hepatitis C NS3/NS4 protease inhibitor in rats

Abstract

1.?The metabolism, pharmacokinetics, excretion and tissue distribution of a hepatitis C NS3/NS4 protease inhibitor, faldaprevir, were studied in rats following a single 2?mg/kg intravenous or 10?mg/kg oral administration of [¹⁴C]-faldaprevir.

2.?Following intravenous dosing, the terminal elimination t_1/2 of plasma radioactivity was 1.75?h (males) and 1.74?h (females). Corresponding AUC_0–∞, CL and V_ss were 1920 and 1900?ngEq?·?h/mL, 18.3 and 17.7?mL/min/kg and 2.32 and 2.12?mL/kg for males and females, respectively.

3.?After oral dosing, t_1/2 and AUC_0–∞ for plasma radioactivity were 1.67 and 1.77?h and 11?300 and 17?900 ngEq?·?h/mL for males and females, respectively.

4.?In intact rats, ≥90.17% dose was recovered in feces and only ≤1.08% dose was recovered in urine for both iv and oral doses. In bile cannulated rats, 54.95, 34.32 and 0.27% dose was recovered in feces, bile and urine, respectively.

5.?Glucuronidation plays a major role in the metabolism of faldaprevir with minimal Phase I metabolism.

6.?Radioactivity was rapidly distributed into tissues after the oral dose with peak concentrations of radioactivity in most tissues at 6?h post-dose. The highest levels of radioactivity were observed in liver, lung, kidney, small intestine and adrenal gland.     

Pharmacokinetics and renal elimination of desferrioxamine and ferrioxamine in healthy subjects and patients with haemochromatosis.

1 Desferrioxamine mesylate (DM) (10 mg kg-1 = 15.24 mumol kg-1) was given by intramuscular injection to five healthy subjects and to six patients with haemochromatosis, after informed consent. 2 Desferrioxamine (DFA), ferrioxamine (FeA), aluminoxamine (AlA), aluminium (Al) and iron (Fe) were measured in plasma, before and 10, 20, 30, 60 min and 2, 4, 6, 8, 12 h after DM injection and in urine collected over a 6 h period the day before and the day of administration. 3 The predominant form in plasma from control subjects was DFA whereas FeA predominated in plasma from patients. In controls, rapid and slow phases of decline in plasma DFA concentrations were found, with half-lives of 1.0 h and 6.1 h, respectively. In the patients, only a single phase of decline was observed, with a half-life of 5.6 h. Total clearances of DFA were 296 ml h-1 kg-1 in controls and 239 ml h-1 kg-1 in patients. 4 The amount of FeA eliminated in urine during 6 h was significantly lower in controls (8.0 +/- 4.6 mumol) than in patients (129.2 +/- 40.0 mumol), with respective renal clearances estimated over 6 h of 516 ml h-1 kg-1 and 1,716 ml h-1 kg-1. DFA elimination was similar in both groups and its renal clearance estimated over 6 h was 91 ml h-1 kg-1 in controls and 85 ml h-1 kg-1 in patients. 5 Since there was no overlap in the 1 h DFA/FeA plasma ratio between controls and patients, this might be useful as an index of iron overload.