用液相质谱法鉴定盐酸半附甲素在大鼠胆汁中I相和Ⅱ相代谢产物

目的：研究盐酸关附甲素在大鼠胆汁中的代谢产物。方法：建立了液相质谱和串联质谱法（LC－MS）对关附甲素及其代谢产物鉴定的方法。大鼠静脉注射盐酸关附甲素后采集胆汁，通过与对照化合物的色谱保留时间、分子离子峰、碎片离子峰和紫外图谱对照从而鉴定I相代谢物。胆汁经过葡萄糖醛酸酶或硫酸酯酶水解，鉴定其水解产物（苷元），从而确定Ⅱ相结合物，再通过LC－MS分离和确定分子离子峰，最后利用MS－MS寻找特征子离子和母离子的方法进行验证。结果：大鼠胆汁中存在I相代谢物关附壬素；Ⅱ相结合物经葡萄糖醛酸酶和硫酸酯酶酶解后，出现关附甲素和关附壬素；LC－MS检测发现胆汁中m/z 606和510两个准分子离子峰，推测分别为关附甲素葡萄糖醛酸苷和关附甲素硫酸酯；经MS－MS鉴定出m/z 606特征子离子m/z 177和m/z 430，进一步确证大鼠胆汁中存在关附甲素葡萄糖醛酸苷。结论：大鼠胆汁中存在I相代谢产物关附壬素，以及Ⅱ相结合物关附甲素葡萄糖醛酸和硫酸结合物、关附壬素葡萄糖醛酸和硫酸结合物。     

高效液相-质谱联用法对盐酸关附甲素在大鼠尿中代谢物的研究

目的研究盐酸关附甲素在大鼠尿中的代谢产物。方法大鼠iv盐酸关附甲素后收集尿,用高效液相-质谱联用方法测定。通过与标准化合物的色谱保留时间、分子离子峰、碎片离子峰对照从而鉴定I相代谢物。通过用葡糖醛酸酶和硫酸酯酶酶解鉴定其水解产物(苷元)从而确定II相结合物。结果大鼠尿中发现I相代谢物关附醇胺和关附壬素;尿经过葡糖醛酸酶和硫酸酯酶酶解后,产生关附甲素和关附壬素。结论盐酸关附甲素在大鼠体内可以转化为关附壬素、关附醇胺、关附甲素葡糖醛酸和硫酸结合物、关附壬素葡糖醛酸和硫酸结合物。经过生物转化,代谢产物的极性增加,药效下降。     

高效液相-电喷雾质谱分析7-羟基黄酮在大鼠体内的代谢产物

目的:研究7-羟基黄酮在大鼠体内的代谢。方法:应用高效液相-电喷雾质谱检测大鼠灌胃7-羟基黄酮后血浆、尿液、胆汁和粪便中的代谢产物。实验采用Zorbax C18色谱柱,二元线性梯度洗脱进行色谱分离,并与电喷雾质谱联用,根据负离子模式的分子离子峰获得化合物相对分子质量信息,推测化合物的可能结构。结果:在大鼠尿液、粪便、血浆、胆汁中检测到原形成分7-羟基黄酮和7-羟基黄酮葡萄糖醛酸结合物,在胆汁或尿中尚检测到7-羟基黄酮硫酸结合物。结论:7-羟基黄酮在大鼠体内主要以Ⅱ相代谢产物葡萄糖醛酸结合物和硫酸结合物的形式存在。     

LC/MSn鉴定咖啡酸在大鼠体内的代谢产物

目的 研究咖啡酸（CA）在大鼠体内的代谢产物。方法 大鼠灌胃（50 mg·kg-1）给予CA后采集0 ~ 4 h尿样,用电喷雾离子阱多级质谱法对CA在大鼠体内的代谢产物进行分析。结果 大鼠灌胃给予CA后,在体内可测到2个原形药的甲基化代谢物、2个原形药的单葡萄糖醛酸结合物、1个原形药的双葡萄糖醛酸结合物、2个原形药的单硫酸结合物、2个甲基化物的葡萄糖醛酸结合物和2个甲基化物的硫酸结合物。结论 CA在大鼠体内广泛代谢,其代谢物的结构有待于进一步分析后确证。     

LC/MSn鉴定咖啡酸在大鼠体内的代谢产物

目的研究咖啡酸（CA）在大鼠体内的代谢产物。方法大鼠灌胃（50mg·kg^-1）给予CA后采集0～4h尿样,用电喷雾离子阱多级质谱法对CA在大鼠体内的代谢产物进行分析。结果大鼠灌胃给予CA后,在体内可测到2个原形药的甲基化代谢物、2个原形药的单葡萄糖醛酸结合物、1个原形药的双葡萄糖醛酸结合物、2个原形药的单硫酸结合物、2个甲基化物的葡萄糖醛酸结合物和2个甲基化物的硫酸结合物。结论CA在大鼠体内广泛代谢,其代谢物的结构有待于进一步分析后确证。     

大鼠体内大豆苷元及其代谢物分布影响因素研究

目的研究大鼠灌胃给予大豆苷元后,多剂量与性别对大豆苷元及其代谢物在大鼠血浆中分布的影响。方法雌、雄大鼠分别单次或多次灌胃给予大豆苷元1.0 mg·kg-1,血浆样品经沉淀蛋白处理,采用LC-MS/MS方法测定血浆样品中大豆苷元及其II相代谢物的质量浓度,采用Winnolin6.4计算各化合物的主要药动学参数,并对获得的药动学参数进行统计分析。结果大鼠多次灌胃给予大豆苷元后,血浆中大豆苷元及其代谢物的AUC_(0-24)明显高于单次给药。多次给药后雌鼠血浆中大豆苷元主要以大豆苷元-7-葡萄糖醛酸结合物和大豆苷元-7-硫酸结合物形式存在,雄鼠血浆中主要以大豆苷元-7-葡萄糖醛酸结合物、大豆苷元-7-硫酸结合物和大豆苷元-7-葡萄糖醛酸-4'-硫酸结合物形式存在。结论多次给药及性别差异明显影响大豆苷元在大鼠血浆中的分布。     

雷公藤甲素和雷公藤红素在大鼠体内的代谢产物分析

大鼠灌胃给予雷公藤甲素与雷公藤红素混合液.采用液相色谱-串联质谱法,在负离子模式下,以一级、二级全扫描方式检测大鼠血清、尿与粪中的代谢产物.在大鼠血清中仅发现原形药物.在尿样中检测到了雷公藤甲素的3种代谢产物,推测分别为其单羟基化代谢产物、环氧化物水解开环代谢产物及谷胱甘肽结合物.在粪中则检测到1种代谢产物,推测为雷公藤甲素的另一单羟基化代谢产物.在尿样中检测到雷公藤红素的1种代谢产物,推测为葡萄糖醛酸结合物;在粪中检测到硫酸结合物.     

HPLC-ESI/MS分析5-羟基黄酮在大鼠体内的代谢产物

目的研究5-羟基黄酮在大鼠体内的代谢产物。方法应用高效液相色谱-电喷雾质谱(HPLC-ESI/MS)检测大鼠灌胃5-羟基黄酮后血浆、尿液、胆汁和粪便中的代谢产物。实验采用Zorbax C18色谱柱,0.05%甲酸乙腈-0.05%甲酸水二元线性梯度洗脱进行色谱分离,并与电喷雾质谱联用,根据正离子模式的分子离子峰获得化合物分子量信息,推测化合物的可能结构。结果仅在大鼠粪便中检测到原形成分,在大鼠尿液、粪便、血浆、胆汁中检测到5-羟基黄酮葡糖醛酸结合物。结论 5-羟基黄酮吸收差,在大鼠体内主要以II相代谢产物葡萄糖醛酸结合物的形式存在。     

高效液相色谱-四级杆飞行时间串联质谱法分析瑞香素在大鼠肠壁的代谢产物

研究瑞香素在大鼠肠壁产生的代谢产物。采用大鼠在体肠灌流模型,分别收集瑞香素0～2 h内的十二指肠、空肠、回肠和结肠灌流液,以液相色谱-四级杆飞行时间串联质谱法分析肠道灌流液中瑞香素的代谢产物。在大鼠十二指肠、空肠、回肠灌流液中共发现瑞香素原形药物和4个代谢产物,分别推测为瑞香素-7-硫酸酯、瑞香素-8-硫酸酯、瑞香素-7-葡糖醛酸结合物和瑞香素-8-葡糖醛酸结合物;而在结肠灌流液中未发现代谢产物。在瑞香素的4个代谢产物中,瑞香素-7-硫酸酯和瑞香素-8-硫酸酯(m/z 257)为首次发现的瑞香素在大鼠体内的Ⅱ相代谢产物,揭示了其在大鼠体内代谢的新途径。     

6，7-双乙酰化黄芩素在大鼠体内的代谢产物研究

研究6，7-双乙酰化黄芩素在大鼠体内的代谢产物。大鼠灌胃给予6，7-X2K,酰化黄芩素后，采用HPLC—DAD和LC／MS^n方法，检测大鼠肠内和血浆中的代谢产物。6,7-双乙酰化黄芩素在大鼠肠内降解为6-单乙酰黄芩素和黄芩素；在大鼠血浆中检测到4种葡萄糖醛酸苷类代谢产物，初步鉴定为6-O-葡萄糖醛酸黄芩素，6-O-甲基-7-O-葡萄糖醛酸黄芩素，6，7-O-双葡萄糖醛酸黄芩素和6-O-葡萄糖-7-O-葡萄糖醛酸黄芩素。首次报道了6，7-双乙酰化黄芩素在大鼠体内的药物代谢，在肠内和血浆中共鉴定了六个代谢产物。     

Identification of phase I and phase II metabolites of Guanfu base A hydrochloride in human urine.

Guanfu base A is a novel arrhythmic drug candidate isolated from the tuber of a traditional Chinese herb. Phase I and Phase II metabolites of Guanfu base A (GFA) Hydrochloride were studied in human urine by means of liquid chromatography mass spectrometry (LC/MSD) and tandem mass spectrometry (MS/MS). For phase I metabolites, Guanfu base I (GFI) was separated by HPLC and identified by comparison with authentic reference for their retention times, molecular ion peaks, fragment ions, and UV spectra. GFA oxide was also indicated to exist in human urine. For phase II metabolites, after human urine was treated either with glucuronidase or sulfatase, GFA occured in the chromatograms. It was suggested that there were GFA glucuronide and GFA sulfate in human urine. Further more, positive molecular ions, m/z 606 and m/z 510, of the two conjugates were detected in human urine by LC/MSD. In addition, characteristic ion of m/z 606 was identified as the precursor ion of m/z 177 [Glucuronic acid+H]+ by using MS/MS. Characteristic ion of m/z 430 [GFA+H]+ was also identified as a product ion of m/z 606 [GFA glucuronide+H]+. It was concluded that there were GFI. GFA oxide, GFA glucuronide and GFA sulfate in human urine.     

Simultaneous determination of GFA and its active metabolites in human plasma by liquid chromatography electrospray ionization mass spectrometry and its application to pharmacokinetic studies

A sensitive and rapid liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) method has been developed and validated for simultaneous quantification of guanfu base A (GFA) and its metabolites guanfu base I (GFI) and guanfu alcohol-amine (AA) in human plasma with phenoprolamine hydrochloride (DDPH) as the internal standard. The analytes were extracted from human plasma by using liquid-liquid extraction with ethyl acetate and the LC separation was performed on a Diamonsil C(18) analytical column (150 mm x 2.1 mm i.d., 5 microm). The MS acquisition was performed in selected ion monitoring (SIM) mode of positive ions. Analysis was carried out in SIM mode at m/z 430.25 for GFA [M+H](+), m/z 388.25 for GFI [M+H](+), m/z 346.25 for AA [M+H](+) and m/z 344.20 for the IS DDPH [M+H](+). The calibration curves were linear over the range of 50-5000 ng/mL for GFA and 5-1000 ng/mL for GFI and AA, with coefficients of correlation above 0.999. The lower limit of quantification for GFA was 1 ng/mL, while for GFI and AA were both 5 ng/mL. The intra- and inter-day precisions (CV) of analysis were within 9%, and the accuracy ranged from 91% to 108%. The overall recoveries for GFA, GFI and AA were about 94.2%, 87.8% and 80.6%, respectively. The total LC-MS run-time was only 5.5 min. This quantitation method was successfully applied to the simultaneous determination of GFA and its metabolites in human plasma for the metabolic study and pharmacokinetic evaluation.     

Identification of phase-I and phase-II metabolites of fluphenazine in rat bile. Intact glucuronide and sulfate conjugates.

In rat bile following ip administration of fluphenazine (FLU) dihydrochloride (20 mg/kg body weight), phase-I metabolites 7-hydroxyfluphenazine (7-HOFLU) and FLU sulfoxide (FLUSO), together with unmetabolized FLU, were isolated and identified by HPLC and fast atom bombardment spectrometry (FAB/MS) and also by comparison with authentic compounds. Two intact glucuronide conjugates of FLU were isolated and identified as phase-II metabolites: 7-hydroxyfluphenazine ring glucuronide (glucuronic acid linked to the aromatic hydroxyl group of 7-hydroxyfluphenazine), and FLU glucuronide (glucuronide linked to the aliphatic group of the side chain of FLU) by HPLC and FAB/MS in comparison with authentic compounds. Further confirmed by FAB/MS were several sulfate conjugates of FLU that were isolated and identified indirectly as phase-II sulfate metabolites: FLU sulfate, 7-hydroxyfluphenazine sulfate and/or 7-hydroxyfluphenazine ring sulfate, and FLU sulfoxide sulfate by HPLC and FAB/MS; their aglycones were identified after sulfatase hydrolysis as FLU, 7-HOFLU and FLUSO. A further phase-II metabolite, for which no authentic standard was available, was tentatively identified as a monoglucuronide of dihydroxy derivative of FLU. To our knowledge, this report provides the first direct evidence of the presence of intact phase-II metabolites of FLU in rat bile.     

R,S-1-(2-甲氧基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪在大鼠血浆中代谢产物的研究

目的研究R,S-1-(2-甲氧基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪(naftopidil，NAF)在大鼠血浆中的代谢产物。方法用LC/MS法对大鼠口服NAF后的血浆样品进行分析，根据检测到的代谢产物与原形药的质谱行为及类似结构化合物的代谢规律，推测可能的代谢产物。合成对照品，通过比较代谢产物和合成对照品的色谱和质谱行为，对I相代谢物予以确认。通过质谱信息及酶水解的方法间接鉴定II相代谢物。结果大鼠血浆中发现I相代谢物：R,S-1-(2-羟基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪(DMN)、R,S-1-(2-甲氧基-4-羟基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪(PHN)，R,S-1-(2-甲氧基苯基)-4-［3-(4-羟基萘-1-氧基)-2-羟基丙基］哌嗪(NHN)及II相代谢物：NAF和NHN与<>-D-葡糖醛酸形成的结合物。结论NAF在大鼠血浆中的主要代谢途径是苯环、萘环羟基化和苯环邻位甲氧基的脱甲基化。此外，萘羟化代谢物和原形药与内源性分子<>-D-葡糖醛酸形成结合物也是原形药的代谢方式之一。     

Characterization of a carbamic acid ester glucuronide of the secondary amine sertraline

In the dog, the major excretory metabolite of the antidepressant sertraline was characterized as sertraline carbamoyl-O-glucuronide. The intact conjugate was isolated from bile by HPLC. The metabolite was labile to beta-glucuronidase and produced sertraline as the single hydrolytic product, based on HPLC and GC-MS analyses. By fast atom bombardment MS analysis, [M+H]+ and [M+Na]+ ions at m/z 526 and 548 were observed, as were the proton and sodium adducts of the aglycone (m/z 350 and 372) due to cleavage of the glycosidic bond and elimination of the glucuronic acid moiety (176 amu). The observed mass of the aglycone was 44 amu greater than sertraline, indicating that a carbamic acid of this secondary amine was conjugated with glucuronic acid. These data suggest that sertraline in solution reversibly associates with CO2 before formation of sertraline carbamoyl-O-glucuronide. This novel amine glucuronide was also identified in human plasma after the oral administration of sertraline to each of seven subjects. The glucuronide was stable in plasma at both acidic and basic pH.     

LC-MS/MS法研究1-[1-(6-甲氧基-2-萘基)乙基]-2-(4-硝基苄基)-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐在大鼠体内的代谢产物

采用液相色谱-串联质谱法对大鼠灌胃1-［1-(6-甲氧基-2-萘基)乙基］-2-(4-硝基苄基)-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(编号P91024)后粪便、尿液、胆汁和血浆中的主要代谢产物进行研究。通过比较给药样品和空白样品的全扫描总离子流色谱和选择离子扫描色谱图差别寻找I相代谢产物；根据其一级和二级质谱图，确定I相代谢产物的分子结构。完全提取I相代谢产物后的样品溶液，再用葡糖醛酸酶酶解，得II相结合物的苷元部分，采用与I相代谢产物鉴定同样方法寻找和鉴定II相代谢产物苷元的结构，进而确证II相代谢产物的分子结构。从大鼠粪便中鉴定出P91024的2个I相代谢物，从胆汁中鉴定出1个I相和5个II相代谢产物，从尿液中鉴定出1个I相和3个II相代谢产物，从血浆中鉴定出4个I相和1个II相代谢产物；并分别分析推测出它们的结构。P91024在大鼠体内被代谢转化为多种产物，利用LC-MS/MS可以快速寻找和鉴定。     

RP-HPLC法同时测定中药关白附中关附甲素、关附壬素和关附辛素含量

目的：建立同时测定关白附中3种二萜生物碱———关附甲素、关附壬素和关附辛素的RP-HPLC分析方法。方法：色谱柱：Zorbax Eclipse XDB-C8柱（2.1 mm×150 mm,5μm）,流动相：庚烷磺酸钠缓冲液（加入0.2%三乙胺,磷酸调至pH 3）-乙腈（梯度洗脱）,柱温：25℃,流速：0.2 mL.min-1,检测波长：205 nm。结果：3种生物碱的相邻色谱峰分离度大于1.5,关附壬素、关附甲素和关附辛素质量浓度分别在0.100～0.502、0.100～0.498和0.100～0.500 g.L-1的范围内与峰面积呈良好的线性关系（r=0.999 9）,其平均加样回收率（n=9）分别为97.29%、101.46%、102.33%。结论：本法分离效果和重复性好,简便易行,可用于关白附药材中3种生物碱的同时定量分析及药材质量控制。     

Characterization of the Phase II metabolites of rutaecarpine in rat by liquid chromatography-electrospray ionization-tandem mass spectrometry

From the authors' previous studies on the Phase I metabolism of rutaecarpine, nine metabolites formed were identified as products of hydroxylation on the aromatic rings in rat liver microsomes. In order to determine the possible metabolic fate of rutaecarpine, the Phase II metabolites of rutaecarpine were characterized in the present study by using liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS). When male Sprague-Dawley rats were treated intravenously with 4 mg kg(-1) rutaecarpine, 16 different Phase I and II metabolites were identified in urine including four sulfate and four glucuronide conjugates. Phase I metabolites of rutaecarpine were identified as four mono-hydroxylated metabolites (M2-5) and four isobaric di-hydroxylated metabolites (M6-9). These metabolites were identical to the in vitro metabolites except one, which was hydroxylated in the aliphatic moiety. In addition, Phase II metabolites were identified as conjugated with sulfate (S1-4) and glucuronide (G1-4). In faeces, 11 different metabolites were identified. The metabolites M8 and glucuronide conjugated (G1-4) were not detected. Structures of all metabolites were confirmed with CID fragmentation spectra of MS(2), MS(3) and retention times by LC/ESI-MS.     

Phase II metabolism of warfarin in primary culture of adult rat hepatocytes.

We used adult rat hepatocytes in primary culture (HPC) as a model system to study the hepatic phase II metabolism of the anticoagulant warfarin. Hepatocytes were isolated by a collagenase perfusion technique and maintained for 24 hr in Waymouth's medium containing 0.1 mM (R)-warfarin. When HPC medium was analyzed by reverse phase high performance liquid chromatography with diode-array detection, 4'-, 6-, and 7-hydroxywarfarin were identified. Several putative conjugates were observed eluting between 13 and 18 min. Treatment of hepatocyte medium with beta-glucuronidase and sulfatase resulted in the loss of five putative conjugates and concomitant increases in 4'-, 6-, and 7-hydroxywarfarin and warfarin, suggesting that these metabolites and warfarin were conjugated. Use of the beta-glucuronidase inhibitor saccharic acid 1,4-lactone enabled the determination of the relative extents of conjugation of each metabolite by glucuronic acid and sulfate. Glucuronidation was the predominant pathway for 4'-hydroxywarfarin, whereas 6-hydroxywarfarin and warfarin occurred mainly as sulfate conjugates. In contrast, 7-hydroxywarfarin was converted to both glucuronide and sulfate conjugates. Exposure of HPC to phenobarbital resulted in a decrease in cytochrome P-450-mediated production of hydroxylated warfarin metabolites; however, an increase in the production of 8-hydroxywarfarin was observed when HPC were exposed to beta-naphthoflavone. Unique conjugation patterns were found when hydroxylated warfarins were substituted for warfarin in HPC medium. Both 7- and 8-hydroxywarfarin were converted to one sulfate and two glucuronide conjugates, whereas 4'-hydroxywarfarin was converted to a single glucuronide conjugate. A spectral library of these conjugates was used to identify the major conjugates of warfarin formed by rat HPC.