Pharmacokinetics,tissue distribution,and excretion of FGF‐21 following subcutaneous administration in rats

As one of the fibroblast growth factor (FGF) superfamily, FGF‐21 has been extensively investigated for its functions and roles since its discovery. It has been demonstrated to be one of the key regulators for glucose and lipid metabolism, and exhibits beneficial effects on cardiovascular disease. However, studies focusing on its pharmacokinetic behavior in vivo as a novel therapeutic agent have not been reported. In the present study, rapid and sensitive analytical approaches including radioactivity assay and assay after precipitation/separation by high performance liquid chromatography (HPLC) were established to determine the content of FGF‐21 tagged with ¹²⁵I in plasma, tissue, and excrement. The results indicated that FGF‐21 were quickly absorbed into systematic circulation and slowly eliminated; C_max and exposure increased in a dose‐dependent manner, exhibiting a typical linear pharmacokinetic pattern. Tissue distribution also confirmed that the kidney is the primary organ for FGF‐21 to be distributed, even though radioactivity of FGF‐21 was recovered in all tissues examined. In addition, the results also supported that urinary excretion was the critical route for FGF‐21 to be eliminated. The study fully clarifies the pharmacokinetic behavior of FGF‐21 and can provide valuable information and support further safety and toxicology development.     

Plasma pharmacokinetics and tissue distribution of [6]‐gingerol in rats

[6]‐Gingerol is one of the pungent components in ginger which has been found to possess various pharmacological effects. However, there is insufficient information on the properties of [6]‐gingerol based on controlled pharmacokinetic studies. The aim of this study was to clarify distribution profiles of [6]‐gingerol in blood and biological tissues of experimental rats. Rats were administered a 240 mg/kg dose of Gs (a ginger extract, containing 53% [6]‐gingerol) by oral ingestion. Plasma samples were collected at 2.5, 5, 7.5, 10, 15, 20, 30, 45 min, and 1, 1.5, 2, 3, 4 h after dosing (eight samples per time point), and brain, heart, lung, spleen, liver, kidney, stomach and small intestine tissues were collected at 5, 15, 30 min and 1, 2, 4 h after dosing (five animals per time point). Samples were prepared by a liquid‐liquid extraction procedure and the extracts were assayed by HPLC‐UV. After per oral application, [6]‐gingerol was absorbed rapidly into the plasma, and the maximal concentration (4.23 µg/ml) was reached after 10 min post dosing. [6]‐Gingerol plasma concentrations declined with time in a biexponential pattern. The elimination half‐time at the terminal phase was 1.77 h and the apparent total body clearance was 40.8 l/h. When administered orally, [6]‐gingerol was well distributed to the tissues examined, with the highest concentrations found in the gastrointestinal tract. Maximal concentrations of [6]‐gingerol were reached in most tissues at 0.5 h post‐dosing. The concentrations of [6]‐gingerol in tissues all were higher than in plasma with corresponding tissue to plasma ratios greater than 1 after 0.25 h post‐dose, showing high tissue partitioning and extensive distribution. Copyright © 2008 John Wiley & Sons, Ltd.     

磷酸川芎嗪乳剂在大鼠体内的药动学及组织分布研究

目的： 通过研究磷酸川芎嗪乳剂在大鼠体内的药动学和组织分布，探究磷酸川芎嗪乳剂的生物利用度和脑靶向性。方法： 大鼠静脉注射50 mg·kg^-1磷酸川芎嗪制剂，给药后，在不同时间采血，最后切除大鼠心脏，肝脏，脾脏，肺，肾，和脑。所有样品均采用液相色谱-质谱/质谱联用法（HPLC/MS/MS）进行检测，用DAS 2.1.1软件使用非房室分析计算药动学参数。结果： 与参比制剂（磷酸川芎嗪注射液）相比，乳剂制剂血浆中的药动学参数无显著差异。在血浆中，乳剂的AUC_0-∞和C_max分别为（4 406.96±977.08）mg·L^-1·min和（52.131±13.61）mg·L^-1。组织分布研究发现磷酸川芎嗪乳剂较参比制剂在脑组织分布更多。结论： 磷酸川芎嗪乳剂在心、肝、脾、肺、肾中有靶向趋势，比参比制剂更易分布在组织中。磷酸川芎嗪乳剂制剂具有脑靶向性。     

Pharmacokinetics and tissue distribution of liposomal etoposide in rats

Precipitation of etoposide and adverse events associated with the co-solvents in intravenous solutions can be avoided by using liposomal etoposide (LE). The pharmacokinetics and distribution of the commercial formulation (ETPI) and LE were compared in rats. The pharmacokinetic profiles were biphasic and similar in the initial phase (C_max, Vd, and t_1/2α). However, LE showed a 60% increase in AUC with a 35% decrease in clearance (p?<?0.05). This decreased clearance resulted in a 70% increase in the MRT of etoposide. The uptake of etoposide from LE was higher in macrophage-phagocytic endowed tissues indicating that LE is superior to ETPI for targeted delivery of etoposide.     

Synthesis of N‐(2‐chloro‐3,4‐dimethoxybenzylideneamino)guanidinium acetate [α‐14C]

¹⁴C‐Labelled N‐(2‐chloro‐3,4‐dimethoxybenzylideneamino)guanidinium acetate has been synthesized as a part of a four‐step procedure which involved decarboxylation of 2‐chloro‐3,4‐dimethoxybenzoic acid by Pb(OAc)₄ to give 2‐chloro‐3,4‐dimethoxy‐1‐iodobenzene, followed by a selective lithiation at the iodine position and electrophilic substitution with N,N‐dimethylformamide [α‐¹⁴C] and final reaction with aminoguanidine bicarbonate. The specific activity was 59 mCi/mmol and the overall yield 49%. Copyright © 2002 John Wiley & Sons, Ltd.     

Pharmacokinetics and tissue distribution of crotonoside

1.?Crotonoside is a bioactive ingredient from Croton Herba with a strong antitumour activity. This study aimed to develop a highly sensitive and selective high-performance liquid chromatography (HPLC) method to quantify crotonoside in biological samples for pharmacokinetics and distribution studies.

2.?Protein precipitation by perchloric acid was used to separate crotonoside from the biological samples, and the recovery rates for crotonoside and the internal standard (luteoloside) were >80%. All calibration curves examining the crotonoside levels in plasma and tissues were linear (all correlation coefficients >?0.99).

3.?The response to crotonoside appeared to be dose disproportional to the maximum plasma concentration and the area under the time–concentration curve in plasma over the range of 12.5–50.0?mg/kg, and crotonoside was highly distributed in tissues after intravenous administration. The highest crotonoside level was detected in the liver (28.79?±?14.96?μg/g), whereas crotonoside was undetected in the brain.     

葛根素纳米结构脂质载体大鼠体内药动学与组织分布

目的:制备葛根素纳米结构脂质载体(葛根素-NLCs),并考察其在大鼠体内的药动学及组织分布特性。方法:采用热熔乳化超声-低温固化法制备葛根素-NLCs,考察了葛根素-NLCs的粒径分布、Zeta电位和形态学性质;研究了葛根素-NLCs在大鼠体内的药动学与组织分布特征。结果:葛根素-NLCs平均粒径为(116.2±34.5)nm,多聚分散系数为0.217±0.024,Zeta电位为(-37.2±3.6)mV,包封率为(87.4±4.3)%。葛根素-NLCs在大鼠体内的AUC_0-t和MRT_0-t分别为葛根素注射剂的3.69和2.13倍;组织分布结果表明葛根素-NLCs在大鼠肝、脾、脑内的相对摄取率分别为葛根素注射液的3.95,3.41和2.30倍。结论:葛根素-NLCs延长了药物在血浆中的滞留时间,在体内具有良好的肝、脾和脑靶向性,可提高药物疗效。     

Current therapy for Lambert–Eaton myasthenic syndrome: development of 3,4-diaminopyridine phosphate salt as first-line symptomatic treatment

Abstract

Background:

Lambert–Eaton myasthenic syndrome (LEMS) is a rare pre-synaptic auto-immune disorder of neuromuscular transmission that is characterised by proximal muscle weakness, depressed tendon reflexes and autonomic dysfunction. This review summarises the clinical symptoms, aetiology, diagnosis and treatment options for LEMS. Focus is placed on symptomatic treatment with the potassium channel blocker 3,4-diaminopyridine (3,4-DAP).     

125I‐Labeled 2‐O‐ and 3‐O‐m‐iodobenzyl,and 6‐O‐m‐iodophenyl derivatives of L‐ascorbic acid: synthesis and preliminary tissue distribution

Three ¹²⁵I‐labeled 2‐O‐ and 3‐O‐m‐iodobenzyl, and 6‐O‐m‐iodophenyl derivatives of L ‐ascorbic acid were prepared by melt exchange procedures in isolated radiochemical yields of 12–60% after HPLC purification. Biodistribution studies in tumor‐bearing mice showed very different in vivo tissue uptake properties from previous results obtained with ¹⁴C‐labeled ascorbic acid and 6‐deoxy‐6‐[¹⁸F]fluoro‐L ‐ascorbic acid. None of these seems to be suitable radioiodinated analogs of L ‐ascorbic acid for imaging study of its in vivo biochemistry. Copyright © 2003 John Wiley & Sons, Ltd.     

超氧化物歧化酶脂质体在大鼠体内的药代动力学和组织分布

目的考察3种超氧化物歧化酶(SOD)脂质体静脉给药后在大鼠体内的药代动力学和组织分布。方法 用反相蒸发法制备SOD脂质体，采用黄嘌呤氧化酶法检测SOD活力，静脉注射给药后，测定大鼠血中SOD含量变化和不同组织中SOD含量变化。结果在血浆中，SOD水溶液、SOD普通脂质体、用DSPE-PEG2000修饰的SOD脂质体、用Tween 80修饰的SOD脂质体的半衰期分别为0.25，0.34，0.66和0.41 h；AUC分别为12.48，24.66，41.16和33.02 μg·h·mL^-1。与普通脂质体比较，经过DSPE-PEG和Tween 80修饰后的脂质体，使肝、脾中SOD的含量有不同程度的降低，脑中含量有所提高。结论3种SOD脂质体均可不同程度地延长SOD的血浆半衰期，并以用DSPE-PEG2000修饰的SOD脂质体效果最好。与普通脂质体相比，用Tween 80修饰的SOD脂质体可以提高进入脑中的SOD量，用DSPE-PEG2000修饰的SOD脂质体可以减少肝脾对SOD的摄取。     

蝙蝠葛苏林碱在兔体内的药代动力学及组织分布

目的:研究蝙蝠葛苏林碱(DS)在兔体内的药代动力学和组织分布特征.方法:兔耳缘静脉注射给予DS后,采用高效液相色谱法测定各时间点血浆和组织器官药物浓度,并用3p97程序计算药代动力学参数.结果:兔DS 2.5、5、10 mg·kg-1静脉注射给药后,体内动力学行为符合二房室开放模型.T1/2β分别为 3.0±0.6、3.4±0.9 和 6.9±0.6 h;Cls分别为 3.1±0.6、3.6±0.4 和 4.4±0.3 L·h·kg-1;Vd分别为 13.1±2.7、18.0±6.2 和 43.6±4.4 L·kg-1;AUC0～t分别为 0.84±0.13、1.41±0.17 和 2.30±0.18 mg·h·L-1.在DS 2.5～5 mg·kg-1范围内主要药动学参数无显著性差异(P>0.05),但DS 10 mg·kg-1静脉注射后,C0超比例增加(P＜0.01),T1/2β明显延长(P＜0.01).结论:在 2.5～5 mg·kg-1范围内DS的消除为线性动力学,而10 mg·kg-1静脉注射后,本品在兔体内的消除未呈线性动力学.组织分布以肺脏含量最高,其次为肾、脾和肝脏.各组织器官中药量均显著高于血浆药物浓度.     

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。     

Carbon‐14 radiolabelling and tissue distribution evaluation of a potential anti‐TB compound

This paper describes a five‐step synthesis of a carbon‐14‐labelled pyrazole compound (11). A total of 2.96 MBq of 11 was obtained with the specific activity of 2242.4 MBq/mmol. The radiochemical purity was >99%, and the overall radiochemical yield was 60% based on the [¹⁴C₆] 4‐bromoaniline starting material. Biodistribution results showed that the radiotracer (administrated orally) has a high accumulation in the small intestine, large intestine and liver of both non‐infected and tuberculosis (TB)‐infected mice. Therefore, this suggests that compound 11 undergoes hepatobiliary clearance. The compound under investigation has been found to be slowly released from the liver between 2 and 8 h. The study revealed that 11 has no affinity for TB cells.     

二甲双胍在大鼠体内的药动学和组织分布

目的研究二甲双胍在大鼠体内的药动学和组织分布。方法大鼠腹腔注射二甲双胍(100 mg·kg~(-1))并在0、10、20、30、60、120、240、480和720 min共9个时间点采集血样(大鼠共3只)和各组织样品(大鼠共27只,每个时间点3个),测定血浆和组织样品中的二甲双胍的浓度。结果AUC为(4 676±s 171)mg·min·L~(-1),CL为(21.4±0.8)mL·min~(-1)·kg~(-1),t(1/2)为(50±5)min,t_(max)为(20.0±1.0)min,c_(max)为(59±4)mg·L~(-1):给药后10 min,所有的组织中都能检测到二甲双胍,给药后12 h,肝脏、肺、脾脏和大脑中已检测不到二甲双胍。结论二甲双弧的血药浓度-时间曲线符合一室模型,在体内叹收快,兮布广泛,清除迅速,且可能主要是由肾脏清除;二甲双胍能够进入大脑。     

Pharmacokinetics,bioavailability and tissue distribution of geniposide following intravenous and peroral administration to rats

In order to characterize the pharmacokinetics, bioavailability and tissue distribution of geniposide following intravenous and peroral administration to rats, a reliable gradient HPLC‐based method has been developed and validated. After p.o. administration of geniposide, the peak concentration of geniposide in plasma occurred at 1 h and plasma geniposide was eliminated nearly completely within 12 h. The AUC_{0→ ∞} values of geniposide were 6.99 ± 1.27 h · µg/ml and 6.76 ± 1.23 h · µg/ml after i.v. administration of 10 mg/kg and p.o. administration of 100 mg/kg of geniposide, respectively. The absolute oral bioavailability (%F) of geniposide was calculated as 9.67%. After p.o. administration of geniposide, the AUC_0→4h values in tissues were in the order of kidney > spleen > liver > heart > lung > brain. This study improved the understanding of the pharmacokinetics, bioavailability and tissue distribution of geniposide in rats and may provide a meaningful basis for clinical application of such a bioactive compound of herbal medicines. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and Anticonvulsant Activity of 6‐Alkoxy‐[1,2,4]Triazolo[3,4‐a]Phthalazines

A new series of 6‐alkoxy‐[1,2,4]triazolo[3,4‐a]phthalazines ( 3a – 3v ) were synthesized and their anticonvulsant activity and neurotoxicity were evaluated by the maximal electroshock test and the rotarod test respectively. Significant anticonvulsant activity was displayed by a number of compounds. The most promising compounds 6‐(4‐chlorobenzyloxy)‐[1,2,4]triazolo[3,4‐a]phthalazine ( 3f) and 6‐heptyloxy‐[1,2,4]triazolo[3,4‐a]phthalazine ( 3s) showed a median effective dose of 7.1 and 11.0 mg/kg, and had protective index value of 5.2 and 8.0 respectively. The two compounds were further found to have potent activity against seizures induced by pentylenetetrazole, isoniazid, thiosemicarbazide, 3‐mercaptopropionic acid but not seizures induced by strychnine, indicating that the two compounds might function by enhancing gamma‐aminobutyric acid neurotransmission.     

克拉霉素脂肪乳剂在大鼠体内药动学和组织分布研究

目的研究克拉霉素脂肪乳剂在大鼠体内药动学和组织中的分布情况,并与克拉霉素注射液相比。方法通过高压均质方法制备克拉霉素脂肪乳剂,通过微生物管碟法测定克拉霉素在大鼠体内血药浓度和组织中药物浓度。结果克拉霉素脂肪乳剂和克拉霉素注射液药-时曲线相似并均符合二室模型,两种剂型的AUC0-t分别为(66.76±16.34)和(59.00±11.20)μg·h/ml。大鼠单剂量静脉注射37.5mg/kg克拉霉素脂肪乳剂和溶液剂后,测定各时间点各组织中药物浓度,以肺为最高。与溶液剂相比,脂肪乳剂提高了脾、肺、肝、肾和脑的药物分布。结论克拉霉素脂肪乳剂与克拉霉素溶液剂血药浓度相似,但脂肪乳剂明显改变了克拉霉素体内组织分布,说明更有助于治疗局部脏器感染。     

基因重组人白细胞介素-2在小鼠的药物动力学和分布(英文)

lodogen法制备~(125)I-rlL-2,放射纯度95％,ⅳ后快速、慢速分布和消除T_(1/2)分别为<2,30—120和6—15h,AUC与剂量呈正比,血尿原药占81±13％,im生物利用度0.57,ⅳ后15min浓度顺序为肝>胆汁>肾>血>肾上腺>>血浆>肺>甲状腺>脾>小肠>肠系膜淋巴结>肠内容>卵巢>心>膀胱>胸腺>粪>肌肉>>睾丸>脑>脂肪,24 h排出80％第2天5％。     

重组人白细胞介素－3在小鼠体内的药代动力学及组织分布

用Ｉｏｄｏｇｅｎ法制备１２５Ｉ－γｈＩＬ－３。产品用ＳｅｐｈａｄｅｘＧ－５０凝胶过滤纯化。流出的组分用ＳＤＳ－ＰＡＧＥ测定纯度。选取放化纯度高于９５％的进行药代动力学研究。在ｉＶ剂量为５００、１０００及２５００ｎｇ·ｍｏｕｓｅ－１的１２５Ｉ－γｈＩＬ－３后，浓度－时间曲线按三房室模型拟合，其快分布相约为２ｍｉｎ。慢分布相约为５０ｍｉｎ。终末消除相为８ｈ左右。ＡＵＣ与剂量呈较好的线性关系（ｒ＝０．９９７０）。ｉｍ１２５Ｉ－γｈＩＬ－３１０００ｎｇ·ｍｏｕｓｅ－１后浓度一时间曲线符合一室一级吸收，绝对生物利用度为０．８８，达峰浓度，时间分别为４２．７６μｇ·Ｌ－１和０．５０ｈ。ｉｖ１５ｍｉｎ后，在肾脏中的浓度最高，２４ｈ内排出约８６％的标记药物。