人组织型尿激酶型纤溶酶原激活剂单次静脉给药大鼠体内半衰期、组织分布及排泄

目的评价人组织型尿激酶型纤溶酶原激活剂(HTUPA)在SD大鼠体内的半衰期、组织分布及排泄。方法以125I为示踪剂标记药物HTUPA,SD大鼠单次静脉注射不同剂量的HTUPA,于给药后各时间点采集眼眶血样、尿粪样本和胆汁样本,以及不同时间点处死的大鼠脏器样本,以放射性同位素示踪结合三氯乙酸沉淀法定量检测血浆浓度,分析药物半衰期、组织分布及排泄率。结果大鼠静脉注射1、2和4 mg/kg的HTUPA,其药物浓度-时间曲线符合二室模型特征,平均分布半衰期(t1/2α)分别为(5.62±4.22)、(6.37±4.93)和(6.57±4.13)min;平均消除半衰期(t1/2β)分别为(49.21±19.36)、(41.17±18.50)和(43.68±28.67)min,且剂量与药时曲线下面积呈正相关(r=0.998 5);单次静脉给药2 mg/kgHTUPA,肝肾组织中含量最高,脑含量最低;96 h经尿液和粪便的累计排泄量占总给药量的79.08%和15.40%,24 h胆汁累计排泄量占总给药量的6.67%。结论 HTUPA作为新一代溶栓候选药,体内分布速度快,半衰期适合。     

氚标记的Bcl-2反义核酸(F951)在小鼠体内的药代动力学实验研究

目的　研究一种新的氚标记的Bcl 2反义寡核苷酸 3H F95 1单次静脉注射后在小鼠体内的药代动力学过程。方法　用氚标记F95 1,用液闪仪检测放射性浓度 ,用 3P87软件判断房室模型 ,计算各种参数。用液闪仪检测3H F95 1在小鼠体内各器官中的分布浓度 ,检测给药后 72h内药物从小鼠尿和粪中排泄的量。结果　3H F95 1单次静脉注射后在小鼠体内的动力学过程符合二室模型 ,3种剂量时主要的参数血浆分布半衰期 (T1/ 2α)在 10～ 15min之间 ,消除半衰期 (T1/ 2 β)在 2～ 4 5h之间。3H F95 1在肾、肝、脾、骨髓中分布浓度高于其它器官 ,在心、肺、脑、肠、皮肤、脂肪、生殖腺中也有低水平的分布。3H F95 1主要经肾从尿中排泄 ,给药后 2 4h内的累积排泄量占给药量的 5 0 47%。3H F95 1从粪中排泄的量甚微。结论　3H F95 1在小鼠体内药代动力学过程的研究为其进一步的开发具有指导价值     

靛玉红大鼠体内吸收药代动力学研究

目的 建立测定大鼠血浆中靛玉红质量浓度的高效液相色谱法,考察靛玉红在大鼠体内的吸收动力学特征.方法 大鼠单剂量口服25mg靛玉红,采用高效液相色谱法测定血浆中靛玉红的质量浓度.结果 靛玉红在大鼠体内分布符合二室模型,主要药物代谢动力学参数分别为峰浓度(Cmax)为(48.63±5.68)ng/mL,达峰时间(Tmax)为(18.76±3.55)h,分布相半衰期(t1/2a)为(38.96±9.51)h,消除相半衰期(t1/2β)为(223.81±154.69)h,0~t药时曲线下面积(AUC0-t)为(2.87±1.33)μg·h/L.结论 所建立的高效液相色谱法灵敏、快速,适用于体内靛玉红的质量浓度测定及代谢动力学研究.     

重组人干扰素α-2b纳米粒小鼠体内药物动力学及组织分布

目的考察小鼠静脉注射重组人干扰素α2b纳米粒后的体内药动学及组织分布。方法小鼠尾静脉注射给药后,采集不同时间血液、肝、肺和肾样品,经处理后,应用双抗体夹心酶联免疫吸附法(ELISA)测定重组人干扰素α2b的血浆及组织中浓度。结果重组人干扰素α2b纳米粒及溶液注射给药,血浆药时数据经3p97药动学程序拟合,均符合一级消除动力学双隔室模型。给予重组人干扰素α2b纳米粒小鼠体内消除半衰期(t1/2β=2.786 h)是溶液剂消除半衰期的(t1/2β=0.599 h)的4.7倍;血药浓度时间曲线下面积纳米粒组是溶液剂组的3.95倍,肝组织中药时曲线下面积纳米粒制剂是溶液剂组的3.8倍。与溶液剂组相比,纳米粒组在肺、肾中的药物分布也显著增加(P<0.001)。结论纳米粒作为重组人干扰素α2b的载体,能够显著延长重组人干扰素α2b小鼠体内消除半衰期,增加其在肝、肺、肾组织中的分布。     

羟丙基-β-环糊精-芒果苷包合物在小鼠体内的药代动力学研究

目的建立测定小鼠血浆中羟丙基-β-环糊精-芒果苷包合物质量浓度的高效液相色谱(HPLC)法,并用于药代动力学研究。方法小鼠一次性灌胃给予3.0 g/kg羟丙基-β-环糊精-芒果苷包合物后,用HPLC法检测不同时间间隔的血药浓度,计算药代动力学参数。结果小鼠一次性灌胃给予羟丙基-β-环糊精-芒果苷包合物后,分布相半衰期(t1/2α)为(8.226±0.972)h,消除相半衰期(t1/2β)为(8.674±1.112)h,药时曲线下面积(AUC)为(3.058±0.836)μg.h/kg。结论 HPLC法简便、可靠,可用于芒果苷包合物药代动力学研究,小鼠体内药代动力学过程符合二房室开放模型。     

放射性同位素示踪法研究2-氟-6-三氟甲基吡啶在大鼠体内的吸收、分布和排泄

目的研究2-氟-6-三氟甲基吡啶(JJBD)在大鼠体内的吸收、分布和排泄。方法采用放射性同位素14C标记JJBD,单次ig给予SD大鼠[14C]JJBD 10和100 mg·kg-1(放射性剂量均为3.7 GBq·kg-1),用液体闪烁计数分析仪(LSC)测定大鼠血浆、组织、胆汁、粪便、尿液和笼具清洗液等样品的总放射性,用Win Nonlin软件按非房室模型计算毒代动力学参数。结果 SD大鼠单次ig给予JJBD 10和100 mg·kg-1的曲线下面积(AUC(0-t))分别为22 548±1579和(203 395±27 586)h·μg Eq.·L~(-1);半衰期(t1/2)分别为15.8±1.0和(14.1±0.9)h;达峰时间(Tmax)分别为4.0±3.0和(6.0±5.0)h;峰值浓度(Cmax)分别为1450±355和(7776±1703)μg·Eq.·L~(-1)。JJBD主要分布于脂肪、肝、肾和胃肠道中,大部分组织在染毒后4 h JJBD达到峰浓度,在肌肉、胸腺、全脑、性腺和脾中未见JJBD分布。染毒后0~168 h,JJBD主要从尿液排出,占染毒量的43.1%;部分从粪便排泄,占染毒量的29.7%;笼具冲洗液占染毒量的9.97%。0~72 h大鼠胆汁的总排泄量占染毒量的28.1%。结论单次ig给予SD大鼠JJBD后,JJBD能够快速吸收入血,缓慢消除,不存在蓄积风险;JJBD在大鼠体内分布较广泛,但在脑中未检出,无法通过血脑屏障;大部分JJBD可经粪尿排泄。     

重组人淋巴毒素α衍生物的药动学研究

目的评价重组人淋巴毒素α衍生物(rhLTα-Da)在大鼠体内的药动学。方法大鼠静脉注射不同剂量125I标记重组人淋巴毒素α衍生物(125Ⅰ-rhLTα-Da)后,采用同位素示踪法检测不同时间点的血液和尿粪标本中的总放射性量,血浆样本同时以三氯乙酸(TCA)沉淀法检测放射性量,分析药动学参数。结果大鼠静脉注射不同剂量(25、75和225μg/kg)125Ⅰ-rhLTα-Da,其血药浓度-时间曲线符合二室模型特征,血浆分布半衰期(t1/2α)分别为0.641、0.677和0.616 h(TCA沉淀法对应的t1/2α为0.626、0.632和0.594 h),消除半衰期(t1/2β)分别为11.356、13.373和16.033 h(TCA沉淀法对应的t1/2β为11.329、14.437和12.891 h),血药浓度-时间曲线下面积(AUC)和剂量呈正相关。结论 rhLTα-Da在大鼠体内的吸收、分布和代谢符合二室模型特征,消除速度较慢,但不易蓄积。     

2′,3′-二脱氢-2′,3′-二脱氧-2-氨基-6-环丙胺基嘌呤核糖核苷在大鼠体内的药物代谢动力学和生物利用度

目的研究2′, 3′-二脱氢-2′, 3′-二脱氧-2-氨基-6-环丙胺基嘌呤核糖核苷(Cyclo-D4G, D4G前药)在大鼠体内经静注和口服的药物代谢动力学特征.方法采用高效液相色谱法测定Cyclo-D4G在大鼠血浆和尿液中的浓度.结果静注后, 血浆中Cyclo-D4G的消除半衰期是0.78±0.14 h (±s), 总清除率为0.90±0.21 L·h-1·kg-1, 原药在尿中的排泄分数约为20%, 稳态分布体积为0.91±0.07 L·kg-1.口服后,血浆中Cyclo-D4G的消除半衰期为0.83±0.13 h (±s),总清除率为3.81±2.03 L·h-1·kg-1,原药在尿中的排泄分数约为9%.Cyclo-D4G的口服生物利用度为26.9%.结论 Cyclo-D4G表现出较好的药代动力学性质和较低的毒性,可以做进一步的动物试验和临床试验.     

头孢呋辛钠在小鼠体内的药代动力学及组织分布研究

目的：通过HPLC探讨注射用头孢呋辛钠在小鼠体内的药代动力学和组织分布。方法：小鼠单剂量背部推注头孢呋辛钠1000mg/kg,在不同时间取其血浆及各组织匀浆液经离心沉淀蛋白后,采用HPLC法测定其药代动力学及组织中药物浓度。结果：背部给药后血浆药—时曲线符合一室开放模型,头孢呋辛钠体内分布迅速,分布半衰期为0.6179h,消除半衰期为2.2098h,AUC为76.3199h.mg/mL,肺、肝脏及肾脏中药物浓度较高。结论：头孢呋辛钠在体内分布广、组织浓度高、消除半衰期。     

内皮素受体拮抗剂CPU-0213血药浓度的HPLC测定法和药动学研究

目的 :建立内皮素受体拮抗剂CPU 0 2 13在小鼠和大鼠血清中的检测方法 ,测定单次静脉注射(iv)CPU 0 2 1380mg·kg-1后在小鼠和大鼠体内的药代动力学。方法 :用HPLC测定小鼠和大鼠血清中的药物浓度 ,3P97程序拟合药动学参数。结果 :CPU 0 2 13在 0 .4～ 2 0 0 μg·L-1的范围内呈良好的线性关系 (r =0 .9998) ,最低检测浓度为 35 μg·L-1。日内差小于 2 .7% ,日间差小于 6 .3% ,方法回收率大于 95 .9%。CPU 0 2 13在小鼠和大鼠体内的药 时数据均符合二室模型 ,消除半衰期分别为 83.0±1.8min和 96 .6± 11.5min。结论 :该方法灵敏、简单 ,专属性强 ,重现性好。单次ivCPU 0 2 1380mg·kg-1后 ,在小鼠和大鼠体内的药代动力学未见种属差异性。     

Stereoselectivity and species difference in plasma protein binding of KE-298 and its metabolites.

In vitro protein binding of KE-298 and its plasma metabolites, deacetyl-KE-298 (M-1) and S-methyl-KE-298 (M-2), was high in rat (>97%), dog (>89%) and human plasma (>99%), respectively. Human serum albumin (>93%) was the main protein involved in the binding to plasma proteins, while the binding to human serum globulins was low (16-33%). The binding of KE-298 and its metabolites in all species of plasma was stereoselective. The (+)-(S)-enantiomers of these compounds bound rat, dog and human plasma proteins to a greater extent than did the (-)-(R)-enantiomers, except that the case of KE-298 was opposite in rat plasma. The stereoselective plasma levels of these compounds in rats, dogs, or humans would likely be due to stereoselective differences in binding to plasma albumin. The protein binding of M-1 in adjuvant-induced arthritis rat plasma was >97%, and the stereoselectivity was similar to the case of normal rat plasma. KE-298 and its metabolites remarkably displaced [14C]warfarin, which bound on albumin in a solution of diluted rat serum albumin. Similarly, there was a displacement of [14C]warfarin in solutions of dog and human serum albumin, and concomitantly the displacement of [14C]diazepam. [3H]Digitoxin was not displaced by any of the enantiomers in each albumin solution. No stereoselectivity was found in displacement by enantiomers of the three compounds. These results suggest that stereoselective protein binding can be attributed to quantitative differences in binding to albumin rather than to the different binding sites.     

Formation of a disulfide protein conjugate of the SH-group-containing metabolite (M-I) of esonarimod (KE-298) and its elimination in rats

The reactivity of the thiol moiety of the active main metabolite (M-I) of esonarimod (KE-298), a novel anti-rheumatic agent, was investigated in rats. After repeated oral administration of 14C-KE-298, the radioactivity decreased rapidly and no tendency towards accumulation was found, in marked contrast to other common SH-group-containing drugs. At 30 min after intravenous administration of 14C-M-I to rats, the concentration of the 14C-M-I plasma protein conjugate in plasma was extremely low at 0.143 nmol mL(-1) (0.66% of total plasma radioactivity). The 14C-M-I plasma protein conjugate that formed in rat plasma was mixed disulfide with plasma protein. After intravenous administration of synthetic 14C-M-I plasma protein conjugate to rats, the radioactivity in plasma decreased rapidly, with the terminal half-life at 6.90 h. In-vitro, the 14C-M-I plasma protein conjugate was readily dissociated by the endogenous thiol compounds, cysteine and glutathione. These results suggest that the reactivity of the thiol moiety of M-I is extremely low. Furthermore, the 14C-M-I plasma protein conjugate decreased rapidly in-vivo, which would be related to interaction with endogenous thiol compounds. These properties of M-I are principally responsible for the zero accumulation in rat tissues. KE-298 could therefore be expected to have reduced adverse effects compared with other SH-group-containing anti-rheumatic drugs.     

Interspecies difference in drug protein binding-temperature and protein concentration dependency: effect on calculation of effective protein fraction

The effects of temperature and protein concentration on the binding of thiopental to bovine and rat serum albumin and to rat plasma were examined using flow and equilibrium dialysis techniques. The effects of temperature and protein concentration were peculiar to each species. The binding of thiopental to rat serum albumin or rat plasma was sensitive to temperatures between 4 and 37 degrees, whereas the binding to bovine serum albumin was sensitive to a protein concentration difference of 0.1-4.44%. Therefore, the effective protein fraction is affected by various sets of binding parameters of albumins determined under various temperatures and protein concentrations. Thus, a semi-predictive method for plasma or tissue binding may be unsuccessful unless proper binding parameters are used.     

Preferential binding of chlordecone to the protein and high density lipoprotein fractions of plasma from humans and other species

The preferential distribution of the relatively nonpolar pesticide chlordecone (CD) to liver rather than to fat tissues in humans suggests that it may be transported in plasma differently from other organochlorine pesticides. The plasma binding of [14C] CD was investigated in vitro in human, rat, and pig plasma and in vivo in rat plasma. Protein and lipoprotein fractions were separated by serial ultracentrifugation. Heparin-manganese precipitation and agarose gel electrophoresis were also carried out to determine whether separation techniques altered CD binding to plasma components. In human plasma, the distribution of [14C] CD among proteins and high density, low density, and very low density lipoproteins (HDL, LDL, and VLDL) was 46, 30, 20, and 6%, respectively. The distribution of cholesterol in the same plasma fractions was 4, 20, 63, and 7%, respectively. In the pig and rat the order of binding was similar to that in humans, with protein greater than or equal to HDL greater than LDL greater than or equal to VLDL. Separation by heparin-Mn precipitation confirmed the results obtained by ultracentrifugation. The distribution of [14C] CD in rat lipoprotein was similar whether the CD was administered in vivo or incubated with plasma in vitro, with approximately 80% bound to HDL, 11% to LDL, and 9% to VLDL in either case. Agarose gel electrophoresis of plasma-bound [14C] CD indicated that albumin was the major component of the protein fraction responsible for CD binding. Preferential binding of CD by albumin and HDL may explain its unusual tissue distribution compared to other organochlorine pesticides such as aldrin and dieldrin, which bind preferentially to VLDL and LDL and distribute preferentially to fat tissues.     

Tissue distribution and plasma protein binding of [14C]phenol in rats

The tissue distribution of [¹⁴C]phenol was examined in the rat after oral administration. High concentration ratios between tissues and plasma were found in liver, spleen, kidneys, adrenal gland, thyroid gland, and lungs. Brain, testes, and skeletal muscle had the least concentrations of radioactivity. The total amount of [¹⁴C]phenol in the body reached a peak 0.5 hr after dosing, with only a trace left at 16 hr. Liver was the tissue that accumulated phenol most significantly; 42% of the body phenol was in liver. In blood, 67 to 85% of the ¹⁴C was in the plasma, with 41 to 50% of the radioactivity in plasma bound to plasma protein and/or other macromolecules.     

Species-dependent enantioselective plasma protein binding of MK-571, a potent leukotriene D4 antagonist

The plasma protein binding of the enantiomers of MK-571 was stereoselective and the stereoselectivity was species dependent. The 12 mammalian species studied could be classified into three groups: those that bind the S-(+)-enantiomer to a greater extent than the R-(-)-enantiomer (human, baboon, monkey, cow, dog, and cat); those that bind the R-(-)-enantiomer more extensively (rat, guinea pig, and sheep); and those that show no stereoselectivity (rabbit, hamster, and mouse). The stereoselective binding appears to have no phylogenetic relationship. Using serum albumin instead of plasma, a similar degree of stereoselective binding was observed for human, dog, sheep, and rat, suggesting that albumin is the major binding component for MK-571 enantiomers, and that species differences in stereoselective binding are likely due to structural differences in the albumin molecule. Displacement studies with [14C] diazepam, [14C]warfarin, and [3H]digitoxin indicated that the enantioselective differences in protein binding are most likely due to the differences in binding affinity rather than to different binding sites.     

西瑞香素与大鼠血浆蛋白结合率的测定

目的采用HPLC法对西瑞香素与大鼠血浆蛋白结合率进行研究。方法采用平衡透析法,结合HPLC法测定西瑞香素的大鼠血浆蛋白结合率。结果西瑞香素在低(0.50 mg.L-1)、中(1.0 mg.L-1)、高(2.0 mg.L-1)3个质量浓度下,其血浆蛋白结合率分别为(91.7±1.8)%、(91.6±1.4)%和(90.7±0.81)%。结论西瑞香素具有较强的血浆蛋白结合率。     

碳酸酐酶抑制剂甲苯磺烷唑胺血浆蛋白结合的特征

目的研究甲苯磺烷唑胺与血浆蛋白结合的特征。方法采用平衡透析法对甲苯磺烷唑胺大鼠和人血浆蛋白结合率进行了测定。结果甲苯磺烷唑胺与大鼠和人的血浆蛋白结合率分别为(96.03±0.10)%和(94.24±0.52)%。结论甲苯磺烷唑胺具有较强的血浆蛋白结合率,无浓度依赖性;大鼠和人血浆蛋白结合率具有种属差异性,大鼠血浆蛋白结合率高于人血浆蛋白结合率。     

超滤法测定喜树碱的血浆蛋白结合率

目的：测定喜树碱的血浆蛋白结合率。方法：采用超滤法结合高效液相色谱法对喜树碱与大鼠血浆以及健康人血浆蛋白结合率进行测定。结果：在1,4,8 μg·mL^-1质量浓度下喜树碱与大鼠血浆的蛋白结合率分别为（96.68±0.45）%,（96.41±0.13）%,（96.09±0.44）%;与健康人血浆的蛋白结合率分别为（95.47±0.27）%,（94.92±0.42）%,（94.72±0.48）%。结论：喜树碱与大鼠和健康人血浆蛋白均有很强的结合,并且在考察浓度范围内喜树碱的血浆蛋白结合率无浓度依赖性,但是存在种属差异。     

Multiple computer-automated structure evaluation model of the plasma protein binding affinity of diverse drugs

A drug protein binding model was constructed on the basis of protein-affinity data for154 drugs. The Multiple Computer-Automated Structure Evaluation program (M-CASE) was used for the construction of the model, which separates the total data set into groups of drugs with common structural features. For each of these groups, a multiparameter Quantitative Structure–Activity Relationship (QSAR) was obtained. The most general structural fragment for all investigated drugs is a part of the phenyl ring. The lipophilicity represented by the octanol–water partition coefficient was also found to be a significant parameter for each local QSAR. The model was shown to be able to predict correctly the percentage of drug bound in plasma for ∼80% of compounds with an average error of only ∼14%. This revised version was published online in August 2006 with corrections to the Cover Date.