9-硝基喜树碱内酯型与羧酸盐型在大鼠体内的药动学与肾排泄研究

目的:比较静脉注射9-硝基喜树碱内酯型与羧酸盐型溶液后大鼠体内药动学和肾排泄情况。方法:采用HPLC法同时测定大鼠血浆中9-硝基喜树碱内酯型浓度与总(内酯型+羧酸盐型)浓度以及尿液中9-硝基喜树碱的总浓度。按4mg.kg-1剂量给大鼠静脉注射9-硝基喜树碱内酯型与羧酸盐型溶液,绘制药-时曲线,并采用DAS 2.0软件拟合药动学参数。按同剂量给大鼠静脉注射9-硝基喜树碱内酯型与羧酸盐型溶液,并在各时间段收集尿液,测定尿液中9-硝基喜树碱原形药物累积排泄量。结果:根据AUC计算,9-硝基喜树碱内酯型与羧酸盐型溶液给药以后内酯型的比例分别为(46.7±8.0)%和(8.8±2.5)%,两者的MRT分别为(21.6±2.1)min与(12.7±5.1)min,Vz分别为(0.91±0.16)L.kg-1与(0.56±0.13)L.kg-1,t1/2分别为(17.2±2.4)min与(13.3±3.9)min,差异均有显著性,但总量的AUC并无明显差别。9-硝基喜树碱羧酸盐型及内酯型给药后累积尿液排泄百分率为(30.3±6.4)%和(8.9±0.8)%。结论:9-硝基喜树碱内酯型与羧酸盐型的体内药动学过程存在显著差异,羧酸盐型给药后的肾排泄量远高于内酯型。     

不同内酯型比例9-硝基喜树碱对胆汁排泄的影响

目的考察9-硝基喜树碱(9-nitrocamptothecin,9-NC)不同形式(内酯型或羧酸盐型)给药对胆汁排泄的影响。方法建立HPLC测定胆汁中9-NC浓度的方法,比较不同内酯型比例的9-NC溶液以4 mg·kg?1剂量静脉注射后大鼠胆汁中原形药物的排泄量。结果静脉注射100%,75%,50%,25%,0%内酯型比例的9-NC在8 h内的胆汁累积排泄百分数分别为(7.03±2.23)%,(13.36±0.83)%,(22.68±4.83)%,(28.01±6.71)%,(32.65±2.82)%。结论 9-NC羧酸盐型更易经胆汁途径排泄。     

HPLC法测定大鼠尿液中9-硝基喜树碱的浓度

目的:建立 HPLC 法测定大鼠尿液中9-硝基喜树碱(9-NC)浓度。方法:尿液样品中加入内标喜树碱后,用甲醇-乙腈(1:1)沉淀后离心取上清液进样。采用 Diamonsil C~(18)柱(250 mm×4.6 mm,5 μm)分离,流动相为乙-1%三乙胺(冰醋酸调 pH 至6.5)(45:55),流速1.0 mL·min~(-1),检测波长370 nm。测定静脉注射3 mg·kg~(-1)9-NC 溶液和其脂质体溶液后大鼠尿液中原形药物的排泄情况。结果:线性范围72～18000 ng·mL~(-1),定量限为72 ng·mL~(-1)。静脉注射9-NC 溶液和脂质体溶液后24 h 尿液中原形药物的累积排泄量分别为给药剂量的5.9%和7.6%。结论:本方法简便实用,定量准确,并成功应用于静脉注射9-NC 脂质体后原形药物肾排泄的研究。     

9-硝基喜树碱内酯型在大鼠体内外的稳定性

目的考察9-硝基喜树碱内酯型在大鼠体内和离体大鼠血浆中的稳定性.方法建立利用HPLC法测定大鼠血浆中9-硝基喜树碱内酯型浓度和总浓度的方法;利用此法测定9-硝基喜树碱在离体大鼠血浆、全血及体内血浆中的内酯型比例变化以及大鼠尾静脉注射后不同时间点的内酯浓度和总浓度;并对体内外实验结果进行比较以确定影响血浆中内酯型稳定性的主要因素.结果9-硝基喜树碱内酯型在大鼠体内的稳定性显著优于体外,在体外全血中的稳定性显著优于血浆.结论血细胞具有稳定9-硝基喜树碱内酯型的作用;药物从血浆中的清除是影响体内大鼠血浆中9-硝基喜树碱内酯型比例的主要因素;9-硝基喜树碱内酯型浓度和总浓度在大鼠体内的药代动力学过程符合二室模型,而羧酸盐型浓度符合一室模型.     

9-硝基喜树碱内酯型在大鼠体内外的稳定性9-硝基喜树碱内酯型在大鼠体内外的稳定性

目的考察9-硝基喜树碱内酯型在大鼠体内和离体大鼠血浆中的稳定性。方法建立利用HPLC法测定大鼠血浆中9-硝基喜树碱内酯型浓度和总浓度的方法；利用此法测定9-硝基喜树碱在离体大鼠血浆、全血及体内血浆中的内酯型比例变化以及大鼠尾静脉注射后不同时间点的内酯浓度和总浓度；并对体内外实验结果进行比较以确定影响血浆中内酯型稳定性的主要因素。结果9-硝基喜树碱内酯型在大鼠体内的稳定性显著优于体外，在体外全血中的稳定性显著优于血浆。结论血细胞具有稳定9-硝基喜树碱内酯型的作用；药物从血浆中的清除是影响体内大鼠血浆中9-硝基喜树碱内酯型比例的主要因素；9-硝基喜树碱内酯型浓度和总浓度在大鼠体内的药代动力学过程符合二室模型，而羧酸盐型浓度符合一室模型。     

9-硝基喜树碱单次灌胃给药后大鼠体内的分布与排泄

目的:建立测定生物样品中9-硝基喜树碱的反相高效液相色谱法,研究其在大鼠体内处置的规律及特点。方法:SD大鼠单次灌胃9-硝基喜树碱3．0 mg·kg~(-1)后摘取组织,收集粪、尿、胆汁,用HPLC方法测定药物浓度,计算累积排泄率。结果:9-硝基喜树碱单次灌胃后在各组织广泛分布,24h内原形药从尿及粪中排泄量24066．3ng,占给药量的1．814%,给药后12h原形药从胆汁中排泄13253．7ng,占给药量的1．62%。结论:9-硝基喜树碱原形药累积排泄率约为3．43%,可能主要以代谢物形式排出体外。     

9-硝基喜树碱在大鼠组织中的分布及内酯稳定性

考察9-硝基喜树碱(9-NC)静脉注射后在人鼠组织中的分布及内酯稳定性.建立了HPLC法间时测定组织和血浆中9-NC内酯浓度和总浓度.大鼠静脉注射9-NC溶液后测定各时间点组织中内酯浓度、总浓度和内酯比例.大多数组织中的9-NC内酯比例明显高于血浆;肝中的内酯比例最低,甚至低于血浆;血浆、肾和小肠中的内酯比例随时问延长而下降.9-NC在肝以外的组织中内酯稳定性显著优于血浆.     

静脉注射不同内酯型比例的羟基喜树碱后原形药物经小鼠尿液和粪便排泄的研究

目的:研究静脉注射不同内酯型比例的羟基喜树碱(HCPT)后原形药物经小鼠尿液、粪便的排泄情况。方法:静脉注射不同内酯型比例(100%,75%,50%,25%,0%)的HCPT溶液。分别收集给药后0~3,3~6,6~9,9~12,12~24,24~48 h的尿液和粪便样品,测定其中原形药的含量。结果:原形药从尿液中的累积排泄量分别为12.81%,20.00%,27.01%,32.75%,41.04%,从粪便中的累积排泄量分别为13.91%,18.58%,24.44%,27.48%,31.30%。结论:小鼠尿液和粪便中HCPT原形药物的累积排泄量与HCPT内酯型比例呈负相关,这可能与药物的极性有关。给药后3 h内药物以尿液排泄为主,3~12 h主要从粪便中排泄,12 h后极少从尿液和粪便中排泄。     

9-硝基20（S）喜树碱在大鼠体内的药物动力学

目的:研究9-硝基喜树碱在大鼠体内的药物动力学及排泄。方法:利用高效液相色谱法对静脉注射或灌胃给药后的大鼠血浆及排泄物样品进行分析。绘制血浆药物浓度-时间曲线,并进行非室模型分析及房室模型拟合。利用线性回归评价药物浓度-时间曲线下面积(AUC)与剂量之间、血浆药物峰浓度(C_(max))与剂量之间的线性关系;不同剂量下的药物半衰期及清除率通过方差分析进行比较。计算原形药物自大鼠体内的排泄量。结果:大鼠分别以1.5、3、6mg/kg静脉给药后,AUC_(o-t)分别为633、1606和3011h·μg·L~(-1);t_(1/2)分别为0.5、0.5和0.7h;大鼠分别以3、6、12mg/kg灌胃给药后,C_(max)分别为203、417和1150μg/L,T_(max)均在0.3h左右,AUC_(o-t)分别为269、439和881h·μg·L~(-1);t1/2分别为1.7、0.9和0.9h。9-硝基喜树碱在大鼠体内的绝对生物利用度为14.6％,这与灌胃及静脉注射两种给药途径下原形药物(胆汁和尿中)累积排泄量之比值相一致。结论:9-硝基喜树碱在大鼠体内动力学过程符合二室模型。静脉给药后,药物在大鼠体内的动力学不依赖于剂量,肾排泄为原形药物的主要排泄途径;灌胃给药后,药物绝对生物利用度低,原形药物大部分经粪排泄。     

吐温80对9-硝基喜树碱脂质体药物动力学性质的影响

目的:考察吐温80对9-硝基喜树碱(9-NC)脂质体体内药物动力学以及内酯型/羧酸盐型平衡的影响。方法:采用薄膜法制备9-NC脂质体以及吐温80修饰的9-NC脂质体;12只大鼠随机分为两组,按1.5 mg.kg-1剂量分别给予9-NC普通脂质体和吐温80修饰的脂质体,于不同时间点取血,处理后测定9-NC内酯型浓度和总浓度(内酯/羧酸盐)。采用统计矩模型利用3P97程序计算药物动力学参数。结果:采用表面活性剂吐温80进行修饰后,9-NC内酯型和总浓度的AUC分别提高了1.47倍和1.65倍,内酯型和总浓度的清除率CL和表观分布容积Vss显著下降(P<0.01)。此外,总浓度的MRT以及t1/2延长(P<0.05)。结论:吐温80修饰使得9-NC内酯型比例有所下降,但没有显著性差异,9-NC吐温修饰对9-NC脂质体具有一定的长循环效果。     

Structure—activity relationship of alkyl 9—nitrocamptothecin esters

AIM: To study the structure-activity relationship of alkyl 9-nitrocamptothecin esters. METHODS: Two alkyl 9-nitrocamptothecin (9NC) esters 5g and 5h were prepared by esterification reactions of 9NC with valeric anhydride and heptanoic anhydride, respectively. Eight 9NC esters 5a-5h were tested for cytotoxicity against human leukemia cell lines HL-60 and U-937. Flow cytometry analysis was used to identify the cell cycle phase targeted by the esters and quantify the extent of ester-induced cell death (apoptosis). RESULTS: Esters 5b and 5c demonstrated great abilities to inhibit growth of the leukemia cells followed by induction of apoptosis; esters 5a, 5e, and 5g induced slight perturbations in the cell cycle at high concentrations; and esters 5d, 5f, and 5h were completely inactive against the cell lines tested. Thus these esters showed the cell anti-proliferative activity in an order of 5b approximately 5c>5a approximately 5e approximately 5g>5d approximately 5f approximately 5h. Esters 5b, 5c, and 5e were tested in vivo against various human carcinomas in nude mice grown as xenografts. Only 5b and 5c showed a significant antitumor activity. Particularly, ester 5b demonstrated an antitumor activity against a broad spectrum of human carcinomas including breast, lung, colon, pancreas, stomach, ovarian, and melanoma, etc. CONCLUSION: These esters act like prodrugs of their parental 9-nitrocamptothecin. High drug doses need to be administered to animals in order to inhibit growth, and induce regression, of human tumor xenografts in nude mice. These compounds may be developed into potent anticancer drugs due to their low toxicity.     

9-硝基喜树碱的稳定性初步考察

目的:研究影响因素试验(光线、温度、湿度)、加速试验、长期试验中9-硝基喜树碱(9-NC)的外观性状、有关物质(12-NC)及含量的变化,初步考察其稳定性。方法:利用高效液相色谱法,通过与对照品比较,观察变化的情况。色谱柱:Eclipse~XDB-C_(18)(4.6 mm×150 mm,5μm);流动相:乙腈-水(28.5:71.5);流速:1.0 mL·min~(-1);检测波长:368 nm;柱温:25℃。结果:9-NC 仅对光不稳定,其外观性状、有关物质及含量在高温、高湿度试验,加速试验和长期试验中无明显变化。结论:9-NC 应当避光保存,保证其相对稳定。     

9-硝基喜树碱自微乳化注射液的研制及其体内药动学行为

目的制备9-硝基喜树碱自微乳化静脉注射给药系统(9-NCME),并考察其在大鼠体内的药动学情况。方法采用伪三元相图确定油相制剂组成,以正交设计优化处方组成,评价了9-NCME制剂的稳定性,并考察了正常大鼠尾静脉注射后体内的药动学行为。结果以注射用大豆油为油相、EPC/Tween80为乳化剂、无水乙醇为助乳化剂等成分组成的新型注射剂9-NCME,在临用前用5%葡萄糖注射液稀释20倍后可自发形成平均粒径38.3±4.0nm稳定微乳,大鼠尾静脉给予9-NCME药动学参数为:t1/2(0.97±0.14h),AUC0–8(372.77±49.62ng·h·mL–1)andMRT(1.40±0.21h),分别是对照溶液剂的1.4、1.65和1.4倍(P<0.01)。结论9-NCME具有较好的物理和化学稳定性,有望成为新型的9-NC静脉注射剂。     

正在研究中的抗肿瘤新药9-硝基喜树碱

9-硝基喜树碱(9-NC)为一个半合成喜树碱衍生物,其药理作用主要表现为对拓扑异构酶Ⅰ的抑制.目前,对9-NC的研究已进入Ⅱ期或Ⅲ期临床试验,具有广泛的抗肿瘤活性,且毒性较低,是极具潜力的抗肿瘤新药.现对其药理作用、药动学、临床前研究等作一综述.     

9-nitrocamptothecin liposome aerosol: lack of subacute toxicity in dogs

9-Nitrocamptothecin (9-NC) dilauroylphosphatidylcholine (DLPC) liposome aerosol was evaluated for potential toxicity in an 8-wk, subacute toxicity study in dogs. Fourteen adult dogs were divided into 2 groups with 10 animals in the 9-NC-DLPC treatment group and 4 animals in the DLPC-only vehicle control group. 9-NC-DLPC was administered to the animals using an Aerotech II nebulizer flowing at 10 L/min. Full-face exposures for 60 min were conducted for 5 consecutive days a week for 8 wk. The estimated deposited aerosol dose was 24.7 microg/kg/day. Animals in the vehicle control group received aerosolized DLPC only. Body weight, food consumption, urinalysis, in-life observations, hematology, plasma chemistry, and necropsy and histopathology were monitored before and during the treatment period and in a subset of animals for 2 wk following the end of treatment. Animals were observed for signs of pharmacologic and/or toxicologic effects three times on days of dosing and once daily on nondosing days. 9-NC-DLPC liposomes administered as a small-particle aerosol were determined to be nontoxic to dogs when given for 5 days/wk, for a duration of 8 wk. DLPC-only liposome also had no toxic effects.     

Disposition of 9-nitrocamptothecin and its 9-aminocamptothecin metabolite in relation to ABC transporter genotypes

Summary Purpose: The source of the pharmacokinetic variability of 9-nitrocamptothecin (9NC) and its 9-aminocamptothecin (9AC) metabolite is unknown. ATP-binding cassette (ABC) transporters have been reported to modulate camptothecin analogues, are associated with camptothecin resistance, and might also affect 9NC and 9AC pharmacokinetics. The aim of this study was to evaluate the functional consequence of known single nucleotide polymorphisms in the transporter genes ABCB1, ABCC2, and ABCG2 on the pharmacokinetic disposition of 9NC and 9AC. Experimental design: Pharmacokinetic and genotyping studies were performed in 55 patients as part of two phase I studies of 9NC in patients with refractory solid tumors, a phase II study of 9NC in patients with advanced colon cancer, and a study evaluating the disposition of 9NC after administration of a single dose under fasting conditions. DNA was isolated from plasma and analyzed for variants in ABCB1, ABCC2, and ABCG2 genes. The ABCB1 1236C>T (n = 43), ABCB1 2677G>T/A (n = 43), ABCB1 3435C>T (n = 43), ABCC2 3972C>T (n = 39), and ABCG2 421C>A (n = 42) variants were analyzed using Pyrosequencing. Results: The ABCG2 421C>A genotype significantly affected the pharmacokinetics of 9AC. The mean 9AC lactone AUC/dose for wild-type (n = 25) and heterozygous (n = 2) patients were 14.3 ng/mL · h and 51.1 ng/mL. h, respectively (P = 0.032). The mean ± SD 9AC total AUC/dose for wild-type (n = 39) and heterozygous (n = 3) patients were 91.9 ± 78.3 ng/mL · h and 129.0 ± 90.5 ng/mL · h, respectively (P = 0.40). 9NC and 9AC disposition were not significantly influenced by variants in ABCB1, ABCC2, and ABCG2, and ABCB1 and ABCC2, respectively (P>0.05). Conclusion: These findings suggest that inter-individual variability in 9AC disposition, but not 9NC, may be influenced, in part, by ABCG2 genotype. In contrast, there was no evidence for a relationship between ABCG2 and the disposition of 9NC, or for relationships between ABCB1 and ABCC2 genotypes and the disposition of 9NC or 9AC. Supported, in part, by grant NCI 2P30 CA47904, grant NIH/NCRR/GCRC/#5M01 RR00056, UO1 GM63340, and a grant from Supergen Inc., Dublin, California