维胺酸大鼠体内的药代动力学

用高效液相色谱法测定了维胺酸在在鼠体内的吸收，分布，排泄，生物利用度及蛋白结合率等药代动力学特性，ＲⅡ３０ｍｇ．ｋｇ＾－１ｉｖ，血清中药物浓度经两次加权的二室模型拟合，Ｔ１／２β为２０．７１ｈ，ＣＬｓ为０．３４Ｌ．ｋｇ＾－１，Ｖｃ为０．９９Ｌ．ｋｇ＾－１ＲⅡ１００及２００ｍｇ．ｋｇ＾－１ｐｏ，经一室开放模型拟合，Ｔ１／２ｋｅ分别１１．９２及１３．０１，ＣＬｓ为０．８７及０．７７Ｌ．ｋｇ＾－１ＰＯ．     

萘哌地尔在大鼠体内的药代动力学

为全面了解萘哌地尔(Naf)在大鼠体内的代谢过程,用反相HPLC-UV法,给大鼠ig10,20,30mg·kg^-1Naf后,测定在不同时间各组织和体液中Naf的含量。结果表明,Naf在大鼠体内药代动力学为二室模型,T_1/2α为0.47～1.01h,T_1/2β为4.78～7.08h,达峰时间T(peak)为0.42～0.90h,Cmax,AUC随剂量升高而增大。给药后15min,肠壁组织浓度最高,其次为肝、肺;2h以后,除睾丸、卵巢和子宫外,其余组织药物浓度逐渐降低。尿、粪及胆汁中原形药总排出量不足给药量的1%,提示Naf在大鼠体内有首过效应及代谢物生成。在100～500mg·ml^-1浓度范围内,Naf血浆蛋白结合率为82%～97%。     

阿德福韦酯在大鼠体内的药代动力学和组织分布特性研究

OBJECTIVEThe pharmacokinetic properties of adefovir dipivoxil were studied in rats. METHODSUpon oral administration of adefovir dipivoxil at 0.3, 1.0, 3.0 mg Kg-1, plasma samples were obtained at intervals during the 24 h postdosing and were analyzed for     

双氯芬酸钠在大鼠体内药代动力学的研究

目的：研究双氯芬酸钠在大鼠体内的药代动力学过程。方法：大鼠口服给药后颈静脉插管术采血，用反相高效液相色谱法测定血浆药物浓度。结果：药代动力学过程符合二室模型，Ａ＝６２６４±２７１７μｇ／ｍｌ，α＝１９８２±０６３５·ｈ－１，Ｂ＝４７１２±３３７１μｇ／ｍｌ，β＝０１６３±００５６·ｈ－１，Ｖｄ＝０５７８±０１８４Ｌ，ｔ１／２／β＝４６２２±１３２２ｈ，Ｔｐ＝０２６４±０１１５ｈ。结论：双氯芬酸钠口服易吸收，分布快而广泛     

延胡索乙素在大鼠体内的立体选择性药代动力学延胡索乙素在大鼠体内的立体选择性药代动力学

目的研究dl-延胡索乙素在大鼠体内的立体选择性动力学过程。方法血浆样品经液-液萃取后，用非手性-手性HPLC联用法测定血浆中延胡索乙素对映体的浓度，配对t-检验比较两对映体的血药浓度和药代动力学参数。结果大鼠血浆中l-延胡索乙素的浓度均明显高于d-延胡索乙素的浓度，两对映体的AUC，MRT和Cmax均有显著性差异。结论大鼠灌胃延胡索乙素消旋体后，两对映体在体内的药代动力学过程具有显著的立体选择性。     

阿德福韦酯在大鼠体内的药代动力学和组织分布特性研究

目的研究阿德福韦酯在大鼠的体内过程特性及绝对生物利用度,为临床合理用药提供依据.方法大鼠随机分组,分别一次性灌胃给药阿德福韦酯3.0,1.0,0.3 mg·Kg-1,静脉注射0.54 mg·Kg-1,采用高效液相色谱法检测阿德福韦在生物样品中的含量,并计算药代动力学参数.大鼠口服阿德福韦酯后于0.7,3,6h测定各组织的药物浓度.口服阿德福韦酯1.0 mg·Kg-1,24h内收集胆汁,测定药物胆汁排出率.用平衡透析法测定药物的人血清蛋白结合率.结果该药药代动力学过程符合无滞后时间的二室模型,高、中、低三个剂量的AUC(0～∞)分别为10.7±1.19,3.91±0.315,1.54±0.074 μg·mL-1·h;tmax在0.62～0.76 h之间,Cmax与给药剂量成正比,分别为2.26±0.299,0.758±0.0529,0.388±0.0269 μg·mL-1;t1/2 为5.0～7.3 h;绝对生物利用度为分别为(53±5.2)%,(51±8.1)%,(42±6.0)%.静脉注射给药阿德福韦后t1/2(ke) 为7.5±0.16 h,AUC(0～∞)为 6.35±1.58 μg·mL-1·h.母体药物阿德福韦在组织中分布情况为肾>肝>胃,其他组织中的浓度均远低于血浆中浓度.胆汁累积排泄率低于2%,在0.10～4.0μg·mL –1的浓度范围内,人血清蛋白结合率为<5%.结论阿德福韦酯在动物体内迅速吸收,消除半衰期较长,胆汁不是该药的主要排泄途径,血液及主要脏器无药物蓄积.阿德福韦是生物样品中检测到的唯一代谢产物.     

普罗布考在高血压大鼠体内药代动力学的研究

目的研究普罗布考在高血压大鼠体内的药代动力学。方法取10只高血压大鼠灌胃给予普罗布考（10mg／kg）,于给药后取体内不同时间（0．5,1．0,1．5,2．0,2．5,3．0,4．0,6．0,9．0h）的血样。用高效液相色谱法测定普罗布考的血药浓度,绘制药-时曲线,采用PKS软件计算药代动力学参数。结果普罗布考在高血压大鼠的药．时曲线符合二室模型,其Tmax为（1．917±2．1）h,Cmax分为（25．61±1．0）μg／ml,t1/2为（2．26±0．01）h。结论采用灌胃普罗布考的大鼠体内药动学呈二室模型,分布较快,代谢较慢。     

Brain pharmacokinetics and tissue distribution of tetrahydropalmatine enantiomers in rats after oral administration of the racemate

Tetrahydropalmatine (THP), a racemic mixture, is a biologically active ingredient isolated from a traditional Chinese herb Rhizoma Corydalis (yanhusuo). The main objective of this study was to determine the brain pharmacokinetics and tissue distribution of THP enantiomers in rats after oral administration of racemic THP (rac-THP). Rats (5 animals/group/per time) were given a single oral dose of rac-THP and killed after different post-treatment times. The concentrations of THP enantiomers in plasma, cortex, cerebellum, diencephalon, brain stem, striatum and hippocampus were measured using a validated chiral high performance liquid chromatographic (HPLC) method coupled with an achiral column. The pharmacokinetic profiles of the two enantiomers in six brain regions were significantly different. The peak concentrations (Cmax) and AUC(0-infinity) values of the (-)-enantiomer were significantly greater than the corresponding values for the (+)-enantiomer while the striatum contained the highest peak concentrations compared with the plasma and other brain regions. The tissue distribution studies also revealed significant differences between the two enantiomers in all tissues except the lung. The highest concentrations of both enantiomers were found in the liver. The (-)/(+)-THP ratios in six brain regions and other tissues were consistent with that observed in plasma indicating that the stereoselective disposition of THP in rat brain and other tissues reflects the situation in plasma.     

大鼠静脉注射丹参酚酸B后的药代动力学研究

目的:建立丹参酚酸B的反相高效液相色谱分析方法,并对其在大鼠体内的药代动力学行为特性进行全面的分析研究。方法:生物样品采用液-液萃取方法,以Hypersil C18ODS色谱柱(200 mm×4 .6 mm,5μm) ,柱温40 ℃,流动相:乙腈水=20 80(含0 .25 mol/L乙酸胺) ,用磷酸调pH至4 .0 ,流速:1 .0 mL/min;紫外检测波长:328 nm。结果:鼠尾静脉给予丹参酚酸B1 .6、3 .2、6 .4 mg/kg后,结果显示鼠α相半衰期为(3 .1±0 .1) min,β相半衰期为(31 .5±3 .2) min。大鼠尾静脉给予丹酚酸B后,组织中浓度依次为(高→低) :心、肝、肺、小肠、肾脏、脾、胃、卵巢和脑组织。丹参酚酸B在粪便和尿中24 h及胆汁中2 h的累积排泄百分数分别约为1.43 %、0.77 %及8 .03%。丹参酚酸B人血浆蛋白结合率和大鼠血浆蛋白结合率分别为89 .2 %±1 .8 %和92 .5 %±1 .5 %。结论:本法准确、稳定、灵敏度高,适合生物样品中丹参酚酸B的分析。丹参酚酸B在大鼠体内消除速度快,血浆蛋白结合率较高,胆汁为其主要排泄途径。     

Pharmacokinetics of amiodarone after intravenous and oral administration

Summary Seven patients with cardiac arrhythmias were given amiodarone 400 mg intravenously over 2 min, and 2–4 days later the same dose was given orally. The serum concentration of amiodarone was determined by HPLC; the sensitivity of the analysis was 0.1 µg/ml. The time sequence of the measurements of drug concentration made conventional compartemental analysis impossible. There was large individual variation but some of the curves suggested enterohepatic circulation. The time from oral intake to the peak serum concentration was estimated to be 7.3±2.9 h (SD). The amount of drug reaching the general circulation in 24 h after oral intake averaged 42% (22–80%). After oral administration of amiodarone 200 mg 8 hourly the serum concentration before the morning dose averaged 0.61 µg/ml after 24 h, 0.76 after 48 h, 1.18 after 1 week and 1.56 µg/ml after 1 month. In one patient, who had been on amiodarone therapy for 8 months, the drug was discontinued and the serum concentration was followed over the next 3 months. The drug elimination curve suggested an elimination half life of 13.7 days. Because of instability in physiological saline protein binding could not be precisely quantitated, but only characterized as strong. No unchanged amiodarone was found in urine. The urinary excretion of iodine over 2 h after intravenous administration suggested that 5% of orally administered amiodarone was eliminated in the urine after biotransformation. No effect of the drug was observed during the first 10 days of treatment. In 2 patients with supraventricular arrhythmia, an excellent response was seen, and in one with ventricular arrhythmia there was a good response.     

Pharmacokinetics and metabolism of neferine in rats after a single oral administration

The present study utilized HPLC and LC-MS approaches to investigate the pharmacokinetics and metabolism of neferine (a bisbenzylisoquinoline alkaloid). The plasma concentration-time curves of neferine (10, 20 and 50 mg/kg, i.g.) showed double absorption peaks with the first peak at 10 min and the second peak at 1 h. The t(1/2) (beta) was 15.6 h, 22.9 h and 35.5 h, for each of these doses, respectively. Neferine distributed rapidly into different organ systems, with the highest concentrations found in the liver, followed by the lung, kidney and heart at doses of 10 or 20 mg/kg. At 50 mg/kg dose, concentrations of the kidney and lung were higher than those of others. Moreover, this compound was mainly metabolized in the liver and converted partially by CYP2D6 to liensinine, isoliensinine, desmethyl-liensinine and desmethyl-isoliensinine.     

Intra-uterine pressure and serum ibuprofen: Observations after oral administration of 400 mg ibuprofen to a patient with primary dysmenorrhoea

Summary Intra-uterine pressure was recorded in a dysmenorrhoeic patient for 10 h before and after administration of a single dose of ibuprofen 400 mg. Bloodsamples were obtained at regular intervals during the recording for determination of the serum concentration of ibuprofen by reverse HPLC. The maximum serum concentration (37.4 µg Ml^–1) was achieved after 1 h and the terminal half-life of ibuprofen was approximately 2 h. A marked reduction in intra-uterine pressure and the severity of pain was recorded 1.5 h following the administration of ibuprofen. Despite low or non-detectable serum concentrations of ibuprofen after 4 h, intra-uterine pressure never regained the level recorded before treatment.     

两种布洛芬缓释制剂在健康人体内的药物动力学

目的：本文对布洛芬缓释片和胶囊在健康志愿者中的药物动力学进行研究。方法：建立了一个测定人血中布洛芬的高效液相色谱法。结果：口服单剂量６００ｍｇ片剂和胶囊的ＡＵＣ分别为１５０．２±３４．８和１５１．８±３４．５μｇ·ｈ·ｍｌ－１；Ｃｍａｘ分别为２２．７±５．３和２２．２±３．９μｇ·ｍｌ－１；Ｔｍａｘ分别为３．５±０．７和３．８±０．８ｈ。口服多剂量６００ｍｇ达稳态后片剂和胶囊的ＡＵＣ分别为１５６．０±３８．７和１６３．２±４４．７μｇ·ｈ·ｍｌ－１；Ｃｍａｘ分别为２４．６±５．５和２３．８±４．４μｇ·ｍｌ－１；Ｔｍａｘ分别为３．０２±０．２９和３．２±０．５ｈ。达稳态后片剂和胶囊的波动系数分别为１．４±０．３和１．４２±０．２３。经统计学处理，上述各参数间差异均无显著性（Ｐ＞０．０５）。结论：双单侧ｔ检验（ＮＤＳＴ程序）的结果表明，布洛芬两种缓释制剂具有生物等效性。     

口服和静注丹参素在兔体内的药动学

目的:研究家兔灌胃丹参提取物和静注丹参素溶液后丹参素在体内药动学特征.方法:用高效液相色谱(HPLC)法测定了16只家兔按丹参素10 mg·kg-1单剂量灌胃丹参提取物和静脉注射丹参素溶液后,丹参素血药浓度变化情况.结果:HPLC法的线性范围为0.114～5.68 mg·L-1,r=0.999 8.平均相对回收率为96.8%～101.3%,RSD为1.7%～6.2%,日内、日间精密度RSD分别为3.2%～8.1%和3.3%～8.8% ;经口给药丹参素主要药动学参数T1/2(Ke)为(1.24±0.20 )h,Tmax为(1.25±0.15) h,Cmax为(0.86±0.19 )mg·L-1,AUC(0-7)为(2.95±0.71) mg·h·L-1.静注丹参素主要药动学参数T1/2β为(1.69±0.38) h,AUC(0-7)为(4.37±0.49) mg·L-1·h.结论:经口给药丹参素在兔体内过程符合一室开放模型,吸收较完全,可作为口服应用.     

Pharmacokinetics of metformin after intravenous and oral administration to man

Summary The kinetics of¹⁴C-metformin have been studied in five healthy subjects after oral and intravenous administration. The intravenous dose was distributed to a small central compartment of 9.9±1.61 ( ±SE), from which its elimination could be described using three-compartment open model. The elimination half-life from plasma was 1.7±0.1 h. Urinary excretion data revealed a quantitatively minor terminal elimination phase with a half-life of 8.9±0.7 h. After the intravenous dose, metformin was completely excreted unchanged in urine with a renal clearance of 454±47 ml/min. Metformin was not bound to plasma proteins. The concentration of metformin in saliva was considerably lower than in plasma and declined more slowly. The bioavailability of metformin tablets averaged 50–60%. The rate of absorption was slower than that of elimination, which resulted in a plasma concentration profile of flip-flop type for oral metformin.     

Pharmacokinetics of oltipraz after intravenous and oral administration in rats with dehydration for 72 hours

Pharmacokinetic parameters of oltipraz were compared after intravenous and oral administration at a dose of 30 mg/kg to control rats and rats with water deprivation for 72 h (rats with dehydration). The plasma protein binding of oltipraz was measured in both groups of rats using an equilibrium dialysis technique. The concentrations of oltipraz were measured by the reported HPLC analysis. After intravenous administration, the total area under the plasma concentration-time curve from time zero to time infinity (AUC), terminal half-life, time-averaged total body and nonrenal clearances, and apparent volume of distribution at steady state were not significantly different between the two groups of rats. However, after oral administration to rats with dehydration, the AUC was significantly smaller than that in control rats (180 versus 316 microg min/ml) mainly due to decrease in absorption. In rats with dehydration, plasma protein binding was significantly greater than that in control rats (91.5 +/- 0.309 versus 81.3 +/- 2.79%).     

Pharmacokinetics of single oral and multiple intravenous and oral administration of acebutolol enantiomers in a rat model

Acebutolol (AC), is a chiral, β -adrenergic blocking agent which possesses partial agonist activity and is metabolized to an equipotent chiral metabolite, diacetolol (DC). The enantiomeric disposition of AC is reported following racemic administration as a single oral (p.o., 50 mg kg⁻¹) or as a multiple thrice daily intravenous (i.v.) or p.o. dosing for four days in male Sprague–Dawley rats (n =6). Enantiomeric concentrations of AC and DC in plasma and urine were determined using a stereospecific HPLC assay. The bioavailabilities of R- and S-enantiomer were 0.40 and 0.39 after single dose administration of AC respectively. These values were increased to 0.51 and 0.53 after multiple dosing. Although no significant differences were found in AUC_0–∞ after single i.v. as compared with AUC_0–τ after multiple i.v. dosing of AC, the 39 and 45% increase in mean AUC_0–τ were found after multiple p.o. dosing over the corresponding AUC_0–∞, for the single p.o. dose of AC for R- and S-enantiomer, respectively. The disposition of DC as well as the urinary excretion of metabolite was stereoselective in favor of R-enantiomer after oral administration of AC. These results indicate that AC enantiomers have low availability and moderate extraction through the first-pass metabolism in a rat model. The higher AUC values after p.o. multiple dosing may suggest a saturable first-pass metabolism of AC. © 1998 John Wiley & Sons, Ltd.