Pharmacokinetics and tissue distribution of chlorpheniramine in rabbits after intravenous administration

Intravenous studies of chlorpheniramine (CPM) were conducted in six New Zealand White male rabbits (mean wt. 3.88 kg). CPM and its two demethylated metabolites in arterial serum and urine were assayed by HPLC. Triexponential equations were needed to fit the i.V. CPM serum data in three rabbits, while biexponential equations were required in the other three rabbits. Harmonic mean of V₁, V_ss, V _area , CL,and terminal t _1/2 were 2.84, 10.8, and 15.5 liters/kg, and 4.14 liters/kg/hr and 2.57 hr, respectively. The average serum protein binding was 44%. The average blood to plasma concentration ratio was 1.85. Estimated mean hepatic blood extraction ratio based on i.v. studies was 0.88. Tissue distribution studies showed rapid and extensive uptake of CPM by various organs such as lung, kidneys, and brain after i.v. bolus injection, as their concentrations were 160-, 80-, and 31- fold higher than the plasma level. The amount of CPM in the muscle was calculated to represent about 50% of CPM present in the body near the steady state. Variation in plasma protein and tissue binding was postulated to be an important factor for the observed marked interspecies difference in the apparent volume of distribution of CPM. Only 2% of the dose was excreted unchanged in the urine.     

Pharmacokinetics and tissue distribution of spinosin after intravenous administration in rats

Spinosin is the major effective single constituent in the traditional Chinese herb Semen Ziziphi Spinosae, which is used for sedation and hypnosis. For the further use of spinosin in treating insomnia, the pharmacokinetics and tissue distribution of spinosin after intravenous administration to rats was investigated. An HPLC method with an ODS column (250 mm x 4.6 mm, i.d.) and a mobile phase of acetonitrile-water-acetic acid (23:77:1) was used for the determination of spinosin in the plasma and tissues of rats. Vanillin was used as an internal standard, and spinosin was detected at 334 nm. The calibration curve of spinosin in plasma showed good linearity over the concentration range of 1-300 microg/ml, and the quantitation of limit of plasma was 1 microg/ml. The linear range of concentrations of spinosin in the heart, spleen, stomach, lung, testis, brain, and intestine was 0.1-40 microg/ml and the quantitation limit was 0.1 microg/ml. The linear range of concentrations of spinosin in the liver and kidney was 1-150 microg/ml, and the quantitation limit was 1 microg/ml. The correlation coefficients of all calibration curves were between 0.9939 and 0.9980. The intra and interrun precision for all samples was less than < or =11.0%. The time-concentration curve of spinosin after the intravenous administration of a single dose of 20 mg/kg to rats corresponded to the two-compartment model. The main pharmacokinetic parameters T(0.5alpha), T(0.5beta), CLs, AUC(0-T), and V(c) were 6.66 min, 51.5 min, 1.42 l.min(-1), 2.83 mg.min.ml(-1), and 14.0 l.kg(-1), respectively. At 20 min, a concentration peak occurred in liver and brain tissues. The highest level of spinosin occurred in the liver, followed by the spleen and kidney. The lowest level of spinosin appeared in the testis, followed by the brain. Spinosin was not detected in smooth and skeletal muscle. After intravenous administration, the drug was distributed extensively and transferred quickly in rats in vivo.     

Pharmacokinetics of ipratropium bromide after single dose inhalation and oral and intravenous administration

Single doses of ipratropium bromide were administered intravenously, orally and by slow inhalation to ten healthy male volunteers. The plasma level after oral administration followed a low but broad plateau persisting for several hours. After i.v. administration the kinetic parameters were: Vc = 25.9 l, V alpha = 13.1 l, V beta = 3.38 l, t1/2 alpha = 3.85 min, t1/2 beta = 98.4 min, AUC = 15.0 h.ng/ml, kel = 11.8 l/h and total clearance is 2325 ml/min. The bioavailability was 3.3% (range 0.9-6.1%) on comparing the plasma AUCs following i.v. and 20 mg oral administration. The cumulative renal excretion (0-24 h) after i.v. administration was compared with that after oral administration and inhalation. Following oral administration, the apparent systemic availability was around 2%, and after inhalation it was 6.9%. In comparison with oral placebo administration, only after i.v. administration was there a significant change in heart rate (from 63.7 to 90.2 beats/min). The systolic blood pressure rose from 115.1 to 119.6 mm Hg and the diastolic blood pressure from 68.3 to 78.3 mm Hg.     

Pharmacokinetics of progesterone in ovariectomized rats after single dose intravenous administration.

The pharmacokinetics of progesterone were characterized in ovariectomized female rats. Progesterone was administered intravenously at a dose of 500 micrograms kg-1. Serum progesterone concentrations were determined by radioimmunoassay. Serum concentrations of progesterone were best described by a two-compartment model with elimination from the central compartment. The distribution and elimination phase half-lives were 0.13 +/- 0.024 (mean +/- SD) and 1.21 +/- 0.21 h, respectively. Elimination of the steroid was rapid with a total clearance of 2.75 +/- 0.42 l h-1 kg-1. Progesterone was widely distributed in the rat with a steady state volume of distribution of 2.36 +/- 0.23 l kg-1, a volume of the central compartment of 0.86 +/- 0.24 l kg-1 and a volume of the peripheral compartment of 1.50 +/- 0.19 l kg-1. The results of this study suggest that the ovariectomized female rat is a suitable animal model for examining the pharmacokinetics of progesterone.     

Pharmacokinetics and tissue distribution of galantamine and galantamine-related radioactivity after single intravenous and oral administration in the rat

The plasma kinetics and tissue distribution of galantamine hydrobromide [4aS-(4a alpha,6beta,8aR*)]-4a,5,9,10,11,12-hexahydro-3-methoxy-11-methyl-6H-benzofuro-[3a,3,2-ef] [2benzazepin-6-ol hydrobromide, CAS-1953-04-4], a reversible acetylcholinesterase inhibitor, were studied in male and female non-pregnant and pregnant SPF Wistar rats and in male Fisher x Copenhagen pigmented rats. Most studies were performed using 3H-labelled galantamine hydrobromide, measuring unchanged drug (UD) and non-volatile radioactivity (NVR) in plasma and tissues by high-performance liquid chromatography (HPLC), liquid scintillation counting and quantitative whole-body autoradiography (QWBA). Plasma levels after single intravenous administration of UD (1.25-2.5 mg/kg) declined bi- or triphasically, with an elimination half-life of 3.5 h in male, and 5.1 h in female rats. The plasma clearance (Cl) averaged 1.9 l/kg/h (male rats) and 0.9 l/kg/h (female rats), and the volume of distribution (VdSS) was about 5 l/kg for both male and female rats. Following oral administration (2.5-10 mg/kg), galantamine was rapidly absorbed in both sexes, with an absolute oral bioavailability of 77%. Distribution studies after oral administration of 3H-galantamine showed an almost immediate equilibrium between plasma and tissues, with highest tissue levels of NVR and UD in liver, kidney, salivary glands, adrenal glands and, for the female rat, spleen, and lowest in white fat. To most tissues and especially to brain, the distribution of UD was more pronounced than that of its metabolites. Tissue concentrations of UD and NVR declined at a similar rate as plasma, showing no undue retention. QWBA in the pigmented rat showed the same distribution and elimination pattern of NVR. Only in hair follicles and choroid some retention of NVR was seen, but the calculated half-life was less than one day. In the female pregnant SPF Wistar rat, maternal tissue distribution of NVR was similar to that of the non-pregnant rat. NVR tissue levels in the foetus were similar to those found in maternal blood during the whole experiment, indicating a rapid equilibrium without accumulation.     

Pharmacokinetics and tissue distribution of a new carbapenem,DA-1131, after intravenous administration to mice,rats, rabbits and dogs

The pharmacokinetic parameters including tissue distribution and/or biliary excretion of DA-1131, a new carbapenem, were evaluated after intravenous (iv) administration to mice, rats, rabbits, and dogs. After iv administration to mice (20, 50, 100, and 200 mg kg⁻¹), rats (50, 100, 200, and 500 mg kg⁻¹), rabbits (20, 50, 100, and 200 mg kg⁻¹), and dogs (10, 20, 50, 100, and 200 mg kg⁻¹), the pharmacokinetic parameters of DA-1131 seemed to be independent of DA-1131 doses studied in all four animal species. However, the renal clearance and percentage of iv dose of DA-1131 excreted in 24 h urine as unchanged drug decreased significantly in rabbits (from 200 mg kg⁻¹) and dogs (from 100 mg kg⁻¹) due to reduced kidney function induced by DA-1131. The creatinine clearance decreased significantly in rabbits at 200 mg kg⁻¹ compared with that in the control rabbits (0.466 versus 4.31 mL min⁻¹ kg⁻¹). Renal active secretion of DA-1131 was observed in rabbits and was less considerable in rats, but renal active reabsorption of DA-1131 was observed in dogs. Although DA-1131 was widely distributed in all tissues studied in mice (20–200 mg kg⁻¹), rats (200 mg kg⁻¹), rabbits (50 mg kg⁻¹), and dogs (50 mg kg⁻¹), affinity of DA-1131 for tissues was low: the tissue-to-plasma concentration ratios were greater than unity only in the kidney and/or liver. The low affinity of DA-1131 for tissues was also supported by relatively low values of the apparent volume of distribution at steady state in rats (147–187 mL kg⁻¹), rabbits (91.7–148 mL kg⁻¹), and dogs (243–298 mL kg⁻¹). The contribution of biliary excretion of unchanged DA-1131 to nonrenal clearance of DA-1131 seemed to be minor in rats (200 mg kg⁻¹) and dogs (50 mg kg⁻¹); the percentages of iv dose excreted in 8 h bile as unchanged DA-1131 were 1.76 and 2.71% after iv administration of the drug to rats and dogs, respectively. © 1998 John Wiley & Sons, Ltd.     

Pharmacokinetics and tissue distribution of ipriflavone, an isoflavone derivative, after intravenous administration to rabbits

Pharmacokinetic parameters of ipriflavone and its main metabolites, M1 and M5, after intravenous administration of spray-dried ipriflavone, SIP (10, 20, and 30 mg/kg as ipriflavone) and tissue distribution of ipriflavone, M1, and M5 after intravenous administration of SIP (20 mg/kg as ipriflavone) were evaluated in rabbits. Saturable metabolism of ipriflavone were observed after intravenous administration; at an ipriflavone dose of 30 mg/kg, the dose-normalized (based on 10 mg/kg) AUC was significantly greater (72.4 and 64.0 versus 103 microg min/mL), Cl was significantly slower (138 and 156 versus 97.6 mL/min/kg), and terminal half-life (94.8 and 129 versus 211 min) and mean residence time (91.3 and 116 versus 186 min) were significantly longer than those at 10 and 20 mg/kg. The AUC of M1 was also significantly greater at ipriflavone dose of 30 mg/kg. The terminal half-life, AUC, and renal clearance of M5 were also significantly different at ipriflavone dose of 30 mg/kg than those at 10 and 20 mg/kg. Ipriflavone was widely distributed in most rabbit tissues studied and the tissue-to-plasma (T/P) ratios of ipriflavone were greater than unity in all tissues (or organs) studied except spleen, indicating that ipriflavone has high affinity to rabbit tissues studied, and this could be supported by considerably high values of the apparent volume of distribution of ipriflavone at steady state (11 400-16 900 mL/kg). M1 and M5 were also detected in most rabbit tissues with considerable amount of M1 (T/P ratio of 9.43) and M5 (T/P ratio of 4.66) in the kidney.     

Pharmacokinetics, tissue distribution and bioavailability of nitrendipine solid lipid nanoparticles after intravenous and intraduodenal administration

PURPOSE: The aim of this research was to study whether the bioavailability of nitrendipine (NDP) could be improved by administering nitrendipine solid lipid nanoparticles (SLN) duodenally to rats. METHODS: Nitrendipine was incorporated into SLN prepared by hot homogenization followed by ultrasonication method. SLN were produced using various triglycerides (trimyristin, tripalmitin and tristearin), soy phosphatidylcholine 95%, poloxamer 188 and charge modifiers (dicetyl phosphate, DCP and stearylamine, SA). Particle size and charge measurements were made with a Malvern Zetasizer. Pharmacokinetics of nitrendipine SLNs (NDP-SLNs) after intravenous (i.v.) and intraduodenal (i.d.) administration to conscious male Wistar rats were studied. Tissue distribution studies of NDP-SLNs were carried out in Swiss albino mice after i.v. administration and compared to nitrendipine suspension (NDP-Susp).RESULTS: Average size and zeta potential of SLNs of different lipids, with and without charge modifiers ranged from 101.9 +/- 3.0 to 123.5 +/- 3.0 nm and - 35.1 +/- 0.5 to +34.6 +/- 2.3 mV, respectively. AUC(0-infinity) was increased (up to 4.51-folds) and clearance was decreased (up to 4.54-folds) after i.v. administration of NDP-SLNs with and without charge modifiers compared to NDP-Susp. Effective bioavailability of NDP-SLNs were 2.81-5.35-folds greater after i.d. administration in comparison with that of NDP-Susp. In tested organs, the AUC and MRT of NDP-SLNs were higher than those of NDP-Susp especially in brain, heart and reticuloendothelial cells containing organs.CONCLUSIONS: SLN are suitable drug delivery systems for the improvement of bioavailability of nitrendipine. Negatively and positively charged SLN were better taken up by the liver and brain, respectively.     

Pharmacokinetics of eltoprazine in healthy male subjects after single dose oral and intravenous administration.

The kinetics, safety and tolerability of eltoprazine hydrochloride were studied in an open, cross-over, partially randomised design after single oral (8 mg) and intravenous (3 and 8 mg) doses to 12 healthy male subjects. After intravenous administration, the mean t1/2 ranged from 7 to 9 h, the MRT was 11 h, CL was 487 +/- 148 (3 mg dose) and 471 +/- 56 (8 mg dose) ml kg-1 h-1, while CLR was 226 +/- 124 (3 mg dose) and 189 +/- 38 (8 mg dose) ml kg-1 h-1. The Vss was 3.3 +/- 0.7 (3 mg dose) and 3.8 +/- 0.5 (8 mg dose) 1 kg-1. Cumulative renal excretion was 40%. The AUC and the cumulative urinary excretion were directly proportional to dose within the range of 3-8 mg. Values of tmax varied from 1 to 4 h after oral administration. The mean Cmax value was 24 ng ml-1 after an oral dose of 8 mg. The plasma elimination half-life after oral administration was 9.8 +/- 3.9 h. Absolute oral bioavailability was 110 +/- 32%. Dose-dependent somnolence was observed.     

Pharmacokinetics,tissue distribution and bioavailability of nitrendipine solid lipid nanoparticles after intravenous and intraduodenal administration

Purpose: The aim of this research was to study whether the bioavailability of nitrendipine (NDP) could be improved by administering nitrendipine solid lipid nanoparticles (SLN) duodenally to rats.

Methods: Nitrendipine was incorporated into SLN prepared by hot homogenization followed by ultrasonication method. SLN were produced using various triglycerides (trimyristin, tripalmitin and tristearin), soy phosphatidylcholine 95%, poloxamer 188 and charge modifiers (dicetyl phosphate, DCP and stearylamine, SA). Particle size and charge measurements were made with a Malvern Zetasizer. Pharmacokinetics of nitrendipine SLNs (NDP-SLNs) after intravenous (i.v.) and intraduodenal (i.d.) administration to conscious male Wistar rats were studied. Tissue distribution studies of NDP-SLNs were carried out in Swiss albino mice after i.v. administration and compared to nitrendipine suspension (NDP-Susp).

Results: Average size and zeta potential of SLNs of different lipids, with and without charge modifiers ranged from 101.9 ± 3.0 to 123.5 ± 3.0 nm and ? 35.1 ± 0.5 to +34.6 ± 2.3 mV, respectively. AUC_(0–∞) was increased (up to 4.51-folds) and clearance was decreased (up to 4.54-folds) after i.v. administration of NDP-SLNs with and without charge modifiers compared to NDP-Susp. Effective bioavailability of NDP-SLNs were 2.81–5.35-folds greater after i.d. administration in comparison with that of NDP-Susp. In tested organs, the AUC and MRT of NDP-SLNs were higher than those of NDP-Susp especially in brain, heart and reticuloendothelial cells containing organs.

Conclusions: SLN are suitable drug delivery systems for the improvement of bioavailability of nitrendipine. Negatively and positively charged SLN were better taken up by the liver and brain, respectively.     

Pharmacokinetics and tolerance of a new penem antibiotic,FCE 22101, in healthy volunteers after a single intravenous dose

Summary The clinical tolerance and pharmacokinetics of FCE 22101 (sodium (5R, 6S)-6-[(1R)-hydroxyethyl]-2-carbamoyloxymethyl-2-penem-3-carboxylate), a new penem antibiotic, have been studied after giving a single i.v. dose of 4 mg·kg^–1 to ten healthy male volunteers. The pharmacokinetics was estimated according to a two-compartment open model. The peak plasma concentration (C_max) was 15.5 (1.08) µg·ml^–1, mean (SEM). FCE 22101 was rapidly cleared from the systemic circulation [ =44.2 (4.2) min; CL=7.21 (0.47) ml·kg^–1·min^–1]. The mean apparent volume of distribution at steady-state was 246 (16.9) ml·kg^–1. The mean residence time relative to the 10 min infusion was 39.4 (1.5)min. Urinary recovery of FCE 22101 showed wide inter-subject variation, ranging from 10.2 to 53.6% of the dose. No subject complained of adverse effects.     

Pharmacokinetics of amphotericin B in rats as a function of dose following constant-rate intravenous infusion

Amphotericin B (AmB) is widely used for the treatment of systemic mycoses. The current therapeutic regimens for this drug are complex and somewhat empirical, in part because of very limited information about the disposition kinetics of this agent. In this study, we examined the disposition kinetics of AmB as a function of dose and estimated clearance values using a steady state study design in an animal model. Groups of male Sprague-Dawley rats were given diferent two-step infusion regimens to achieve three different steady state concentrations (i.e., three different total infused doses). We observed no significant differences in systemic clearance among the three AmB doses studied. Similarly, only small differences were seen in volumes of distribution as a function of dose. However, renal clearance decreased significantly as the total infused dose was increased (0.76 ± 0.33, 0.86 ± 0.24, and 0.37 ± 0.04mL min^?1 kg^?1 for the lowmedium and high-dose groups, respectively; p < 0.05). Signs of renal impairment were observed in the high-dose group, as documented by decreased creatinine clearance. Dose-dependent renal clearance may have ben due either to nephrotoxicity associated with the high dose of AmB and/or to saturation of an active secretion process. Furthermore, clearance values estimated from steady state conditions were similar to those from time-averaged values (based on the estimation of area under the plasma concentration-time profile). This suggests that clearance calculations from time-averaged concentrations provide reasonable estimates, since steady state plasma concentrations could be reliably determined. However, the possibility that a true tissue steady state condition was not achieved with our study design cannot be ruled out. Further investigation is necessary to identify the renal excretion mechanisms of AmB and to reach steady state tissue concentration to confirm the estimation of systemic clearance.     

Pharmacokinetics and tissue distribution study of 16-dehydropregnenolone liposome in female mice after intravenous administration

Objective: 16-Dehydropregnenolone (16-DHP) is a potential antitumor compound with poor solubility. A liposome entrapped 16-DHP (16-DHP-LM) formulation was developed to surmount its solubility obstacle. The aim of this study is to investigate the pharmacokinetics of 16-DHP-LM and 16-DHP solution in female mice and tissue distribution of 16-DHP-LM in female tumor-bearing nude mice.

Methods: Rotary-evaporated film method was used to prepare 16-DHP-LM. The comparison of pharmacokinetics between 16-DHP-LM and 16-DHP solution in female mice was investigated after intravenous administration at a single dose of 15?mg/kg. The dose proportionality of 16-DHP-LM was also evaluated after intravenous administration of 16-DHP-LM at the doses of 7.5, 15.0 and 30.0?mg/kg. The tissue distribution of 16-DHP-LM in female tumor-bearing nude mice was evaluated after intravenous administration of 16-DHP-LM at a single dose of 30.0?mg/kg.

Results: The pharmacokinetic study indicated that the 16-DHP-LM group had higher area under the plasma concentration-time curve (AUC), lower apparent volume of distribution (Vz) and smaller systemic clearance (CL) than the 16-DHP solution group. For dose proportionality, good linearity of the pharmacokinetics of 16-DHP after intravenous administration of 16-DHP-LM was observed in the regression analysis of the AUC-dose plot (r?=?0.99) and the C_max-dose plot (r?=?0.98). The tissue distribution study showed that the main tissue depots for 16-DHP in tumor-bearing nude mice were plasma, liver, spleen and tumor, which was benefit to anti-tumor effect. All these results provided a significant basis for the design of clinical trial of 16-DHP-LM.     

Pharmacokinetics and metabolism of diltiazem in rabbits after a single intravenous or single oral administration

Diltiazem (DTZ) 5 mg/kg was given to rabbits either orally (n = 5) or intravenously (n = 6). Plasma concentrations and urinary excretion of DTZ and its metabolites were determined by a high performance liquid chromatography assay (HPLC) for 12 and 48 h post dose, respectively. The results showed that the metabolism and disposition of DTZ in rabbits was similar to that of humans, mean absolute bioavailability (F) of DTZ was approximately 30% and the systemic clearance was 64.0 ml/min/kg. The metabolism of DTZ between the two routes of administration was quantitatively different in that higher plasma concentrations of the metabolites were observed after the intravenous dose. This could be a result of incomplete oral absorption, higher clearance of DTZ and the metabolites during the first pass through the liver (i.e. higher sequential first pass effect), and/or extrahepatic metabolism. On the basis of the plasma concentration-time profiles and urinary excretion of DTZ and its metabolites, it is concluded that the rabbit is a suitable animal model to investigate the kinetics and metabolism of DTZ.     

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 imipramine after single and multiple intravenous administration in rats

Plasma and brain levels of imipramine (IMI) and desmethylimipramine (DMI) in rats after single and multiple iv administration were estimated. IMI accumulated only in plasma, while DMI accumulated in plasma and brain of rats. The brain level of IMI and DMI was higher than plasma level. After multiple administration plasma DMI concentration was significantly greater than IMI concentration. It seems that IMI was obtained steady-state plasma concentration already at fifth day of multiple administration. High dose of IMI (10 mg/kg) caused that the relationship between steady-state concentration and dose of IMI cannot be expressed as a linear function.     

单剂口服盐酸托烷司琼胶囊的人体药代动力学

目的　研究口服单剂盐酸托烷司琼胶囊人体药代动力学。方法　22名健康志愿者口服盐酸托烷司琼胶囊,18例剂量为10 mg, 4例剂量为20mg,于给药后设定时间点采血, 用反相高效液相色谱法-二极管阵列紫外法测定受试者血浆中的盐酸托烷司琼浓度, 并对盐酸托烷司琼的血药浓度-时间数据进行拟合,求算其药代动力学参数。结果　10和20 mg剂量组盐酸托烷司琼胶囊的药代动力学参数分别为:达峰时间tmax为(2.53±0.52)和(2.35±0.90) h;Cmax为(10.16±2.89) 和(19.56±4.04) mg.L-1,曲线下面积AUC0-24h 分别为(113.61±40.34)和(213.36±42.53) mg.h.L-1。结论　单剂量给药,盐酸托烷司琼胶囊在志愿者体内分布及消除较快,且Cmax及AUC与剂量成正比。     

单剂量和多剂量巴洛沙星片在健康人体内的药动学特征

目的研究巴洛沙星片在10名健康志愿者体内的药动学特征。方法5名男性、5名女性健康志愿者单剂量和多剂量口服巴洛沙星片100 mg,采用Waters OASISTMHLB固相萃取小柱提取样品,反相高效液相色谱法测定血药浓度。结果主要药动学参数:单剂量为女t1/2(7．26±2．02)h、ρmax(1 229．93±419．98)μg·L-1、AUC0→48(10 031．56±2 856．78)μg·h·L-1;男t1/2(10．21±1．93)h、ρmax(989．37±219．62)μg·L-1、AUC0→48(9 783．05±879．95)μg·h·L-1。多剂量为女t1/2(8．53±1．84)h,ρav (690．28±150．0)μg·L-1,AUCss(8 283．30±1 800．08)μg·h·L-1,DF(1．68±0．68);男t1/2(8．72±1．23)h、ρav(784．74±82．62)μg·L-1、AUCss(9 416．93±991．41)μg·h·L-1、DF(1．19±0．15)。结论用DAS 2．0软件进行房室模型拟合,巴洛沙星体内过程符合一级消除二室模型,每次100mg,bid连续5 d,可达到稳定有效血药浓度。     

Pharmacokinetics of bencyclane after single dose administration to healthy volunteers

The pharmacokinetics of bencyclane were studied in 4 healthy volunteers. In a randomized cross-over design, 35 and 70 mg of bencyclane were infused intravenously and 71 and 143 mg were given orally as a solution in water. After intravenous application bencyclane is distributed very rapidly into tissues (t1/2 approx. 7 min). The volume of distribution is about 600 l. In almost every subject the plasma levels rose again after this distribution phase. Bencyclane is eliminated mainly by metabolism. At the most 3% of the dose is excreted as unchanged drug in the urine. Total clearance is appr. 44 l/h, the elimination half-life approx. 12 h. Oral bioavailability ranges between 18 and 84%.