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1.
目的 建立液相色谱-串联质谱法(LC-MS/MS)测定大鼠肝微粒体中对乙酰氨基酚含量,研究人参多糖、贻贝多糖、黄原胶对大鼠肝微粒体细胞色素P450(cytochrome P450,CYP)1A2的体外抑制作用。方法 以格列齐特为内标,建立LC-MS/MS测定大鼠肝微粒体中对乙酰氨基酚含量方法。以α-萘黄酮为阳性对照药,分别将系列多糖溶液、CYP1A2酶的特异性探针底物非那西丁及大鼠肝微粒体进行孵育,LC-MS/MS测定代谢产物对乙酰氨基酚的含量,计算半数抑制浓度(IC50),评价人参多糖、贻贝多糖、黄原胶对大鼠肝微粒体CYP1A2酶的抑制活性。结果 对乙酰氨基酚在10~1 000 ng·mL-1内线性良好,精密度试验RSD均<8.24%,提取回收率为92.53%~103.23%,稳定性试验RSD均<10.77%。该试验条件下,在大鼠肝微粒体温孵体系中,人参多糖、贻贝多糖、黄原胶对CYP1A2的IC50值均>100 μmol·L-1结论 在正常剂量下,人参多糖、贻贝多糖、黄原胶对CYP1A2酶亚型均无抑制作用,可以与其底物联合用药。  相似文献   

2.
目的 研究瑞格列奈在大鼠肝微粒体中的酶促反应动力学,并考察氯沙坦钾对其在大鼠肝微粒体中代谢的影响。方法 建立大鼠肝微粒体体外孵育体系对瑞格列奈的代谢进行研究;以洛伐他汀为内标,应用UPLC测定大鼠肝微粒体中瑞格列奈的浓度。采用底物减少法,通过GraphPad Prism 5.0软件计算瑞格列奈的酶促反应动力学常数VmaxKm;分别以系列浓度氯沙坦钾(2.5~50μmol·L-1)与瑞格列奈(44 μmol·L-1)于37℃水浴中共同孵育,并测定肝微粒体中瑞格列奈的减少量,考察氯沙坦钾对瑞格列奈的抑制作用。结果 瑞格列奈在大鼠肝微粒体的最佳孵育时间为40 min,最佳蛋白质量浓度为1 mg·mL-1;瑞格列奈酶促反应动力学参数Vmax=47.29μmol·min-1·(mg·protein)-1Km=51.41 μmol·L-1;氯沙坦钾对瑞格列奈在体外肝微粒体抑制作用的IC50值为17.89 μmol·L-1结论 氯沙坦钾对瑞格列奈在大鼠肝微粒体中的代谢具有较强的抑制作用,两药联合应用可能发生相互作用,具有诱发低血糖的风险。  相似文献   

3.
目的 研究6种药物对有机阴离子转运多肽OATP1B1及其基因多态性A388G、T521C转运作用的影响。方法 体外培养稳定高表达OATP1B1和OATP1B1基因多态性A388G、T521C的人胚肾细胞(HEK293)株,高表达空白载体(Mock)的HEK293细胞为空白对照,实时荧光定量PCR(qRT-PCR)法检测各转运体细胞中mRNA表达;放射性标记化合物3Hestrone sulfate作为转运底物、利福平作为阳性抑制剂验证各高表达细胞的转运活性;测定30 μmol·L-1的达比加群、辛伐他汀、替格瑞洛、卡培他滨、多西他赛、依那普利对各细胞3H-estrone sulfate摄入活性的抑制作用,并依据抑制试验结果,进一步测定辛伐他汀、替格瑞洛、多西他赛对转运体细胞的半数抑制浓度(IC50)。结果 HEK293细胞内导入的各种转运体基因都呈现良好的复制表达;OATP1B1、OATP1B1/A388G、OATP1B1/T521C对底物3H-estrone sulfate(5 μmol·L-1)的转运活性分别为Mock细胞的39、49和48倍,30 μmol·L-1利福平添加后,可将细胞的转运活性抑制到50%以下;辛伐他汀、替格瑞洛、多西他赛对OATP1B1的抑制作用较强,30 μmol·L-1给药的转运活性分别为对照组的(40.09±1.95)%、(33.82±0.61)%、(45.08±0.22)%;辛伐他汀对OATP1B1、OATP1B1/A388G、OATP1B1/T521C的IC50分别为14.2、>100、>100 μmol·L-1,替格瑞洛的IC50分别为19.1、68.4、>100 μmol·L-1,多西他赛的IC50分别为17.6、22.9、19.3 μmol·L-1结论 OATP1B1基因多态性在一定程度上改变了抑制剂对转运体活性的影响程度。  相似文献   

4.
李丹  韩永龙  余涛  宋金春  余奇  郭澄 《中国药师》2014,(8):1259-1263
摘 要 目的:研究常用中药单体及其制剂对CYP3A活性的抑制作用。方法: 在体外肝微粒体孵育体系中加入底物睾酮和不同浓度的中药单体或其制剂,以高效液相色谱法检测6β羟基睾酮的生成量,计算CYP3A酶活性。用GraphPad Prism v5.0软件,按照非线性回归计算出药物对CYP3A抑制作用的IC50值。结果:不同中药单体及其制剂对CYP3A抑制作用的IC50值如下:大黄酸IC50值为36.74 μmol·L-1;大黄素IC50值为23.09 μmol·L-1、芦荟大黄素IC50值为23.91 μmol·L-1,蜂胶IC50值为60.3 μg·mL-1;水飞蓟素胶囊IC50值为24.5μg·mL-1;丹参酮ⅡA磺酸钠注射液IC50值为0.14%(v/v);五味子酯甲IC50值为0.56 μmol·L-1结论: 大黄中的蒽醌、五味子酯甲、蜂胶、水飞蓟胶囊以及丹参酮ⅡA磺酸钠注射液在体外对鼠或人肝CYP3A酶具有抑制作用,临床上使用相关制剂时应密切关注其可能引起的药物相互作用。  相似文献   

5.
秦梦楠 《中国药师》2012,15(2):147-150
摘 要 目的:研究灯盏花素注射液对大鼠肝微粒体CYP1A2、CYP2C9、CYP2D6、CYP2E1和CYP3A1/2 五个亚型酶活性的影响。方法: 采用大鼠肝微粒体体外孵育法,选用非那西丁(CYP1A2)、甲苯磺丁脲(CYP2C9)、右美沙芬(CYP2D6)、氯唑沙宗(CYP2E1)和睾酮(CYP3A1/2)作为5个亚型酶的探针药物,孵育系统中加入不同浓度的灯盏花素注射液,用HPLC法测定5个亚型酶探针药物代谢产物的生成量,比较空白对照组与不同浓度灯盏花素注射液给药组探针药物的活性,反映灯盏花素注射液对5个亚型酶活性的影响。结果:大鼠肝微粒体体外孵育系统中,灯盏花素注射液对大鼠CYP3A1/2的IC50为29.40μg·ml-1,Ki为37.78 μg·ml-1;对CYP1A2、CYP2C9、CYP2D6和CYP2E1的IC50>200 μg·ml-1结论:灯盏花素注射液对大鼠体外肝微粒体CYP3A1/2有弱的抑制作用,对CYP1A2、CYP2C9、CYP2D6和CYP2E1活性无明显影响。  相似文献   

6.
目的 设计、合成杂环二茂铁衍生物,并研究其抗三阴性乳腺癌活性。方法 以二茂铁查耳酮为先导化合物,对其进行结构改造,合成了一系列含有杂环的二茂铁衍生物,并通过CCK8试剂盒测试化合物抗乳腺癌活性。结果 合成了28个二茂铁衍生物,其结构均通过1H-NMR和MS加以确证。初步的生物活性测试结果表明,所合成的二茂铁衍生物对三阴性乳腺癌MDA-MB-231细胞有较强的选择性和抑制活性,其中咪唑杂环化合物抗肿瘤活性强于相应的吡唑类和嘧啶化合物。尤其是28a[IC50=(1.6±0.23)μmol·L-1]对MDA-MB-231的抑制活性分别是先导化合物3[IC50=(10.7±1.41)μmol·L-1]和他莫昔芬[IC50=(13.7±1.17)μmol·L-1]的6和10倍,同时这些二茂铁衍生物对正常乳腺上皮细胞MCF-10A均没有毒性。结论 本研究为开发具有抗三阴性乳腺癌活性的化合物提供了信息和依据。  相似文献   

7.
目的 基于胆红素代谢酶UDP-葡萄糖醛酸转移酶1A1(UGT1A1)靶点评价何首乌中二蒽酮类成分的潜在肝毒性。方法 采用Discovery Studio 2.5软件的From Receptor Cavities模块对UGT1A1酶蛋白空腔进行自动识别,将反式-大黄素-大黄素二蒽酮(trans-EMD)、顺式-大黄素-大黄素二蒽酮(cis-EMD)与UGT1A1酶蛋白进行对接,确定待测单体与酶蛋白的作用方式以及连接的紧密程度;应用大鼠肝微粒体孵育体系,加入底物胆红素对照品溶液,评价trans-EMD、cis-EMD(0.037、0.110、0.330、0.990、2.970 μg·mL-1)对UGT1A1酶的作用,同时启动Ⅰ、Ⅱ相代谢,以表观抑制常数(Ki)为评价指标;CCK-8法检测trans-EMD、cis-EMD(0.04、0.10、0.30、1.00、3.00 μg·mL-1)作用24 h对HepaRG细胞的毒性作用;实时荧光定量PCR(qRT-PCR)实验检测trans-EMD、cis-EMD(0.04、0.30、3.00 μg·mL-1)作用24 h对HepaRG细胞UGT1A1 mRNA水平的影响。结果 分子对接实验显示trans-EMD、cis-EMD可与UGT1A1结合于site F,2个化合物10或10''位不同氢键构型可引起化合物空间构型的改变,影响其与UGT1A1的结合强弱;体外酶抑制实验表明trans-EMD、cis-EMD对UGT1A1酶均表现出竞争型抑制作用,抑制作用较强;细胞毒性实验表明trans-EMD(IC50为1.333 μg·mL-1)和cis-EMD(IC50为1.715 μg·mL-1)均表现出较明显的HepaRG细胞毒性,IC50值较小;与对照组比较,trans-EMD和cis-EMD 0.30、3.00 μg·mL-1均可显著下调UGT1A1 mRNA表达水平(P<0.05),且作用存在浓度相关性。结论 具有大黄素(10→10'')大黄素或大黄素(10→10'')大黄素母核结构的二蒽酮化合物是一类具有潜在肝毒性的化合物,其毒性作用可能与抑制胆红素代谢酶UGT1A1相关。  相似文献   

8.
目的 从民族药山胡椒内生真菌Trichoderma sp.SHJN1和Perenniporia sp.SHJG1的代谢物中寻找活性先导化合物。方法 采用正相硅胶、反相硅胶、Sephadex LH-20凝胶及制备型HPLC等对Trichoderma sp.SHJN1和Perenniporia sp.SHJG1发酵物进行分离纯化,再通过NMR、ESI-MS等鉴定化合物结构,同时采用人乳腺癌细胞(MCF-7)和人肺癌细胞(A549)对这些化合物的抗肿瘤活性进行初步评价。结果 从2株内生真菌次级代谢产物中共分离鉴定了12个化合物:alantrypinone (1)、oryzalactam (2)、phomoindene A (3)、cis-gregatin B (4)、huaspenone B (5)、stigmasta-7,22-dien-3β,5α,6α-triol (6)、ergosterol (7)、1-deoxy-2-demethylviridiol (8)、viridiol (9)、trichodermamides A (10)、chromone (11)、对-羟基苯乙酸(12)。抗肿瘤活性评价结果显示,化合物3 抑制MCF-7细胞增殖活性IC50为(62.9±1.02)μmol·L-1[顺铂(cisplatin,DDP) IC50为(30.1±1.67)μmol·L-1];化合物89 抑制A549细胞增殖活性的IC50分别为(34.6±1.57)μmol·L-1和(44.9±1.74)μmol·L-1[DDP IC50为(20.6±1.42)μmol·L-1]。结论 化合物389 具有潜在抗肿瘤活性。  相似文献   

9.
目的 应用体外实验方法筛选淫羊藿次苷Ⅱ在肝微粒体中的尿苷二磷酸葡萄糖醛酸转移酶(UGT)抑制剂,为改善淫羊藿次苷Ⅱ生物利用度提供新思路。方法 首先选择槲皮素、山柰酚、桔皮素、柚皮素、水飞蓟素、草质素、胡椒碱、甘草查尔酮A以及异银杏双黄酮作为抑制剂筛选对象,对以上9种化合物在人肝微粒体、人肠微粒体、大鼠肝微粒体、猴肝微粒体及小型猪肝微粒体中对淫羊藿次苷Ⅱ葡萄糖醛酸化反应的抑制作用进行初步研究。抑制剂分别选择低、中、高3个浓度(1、10、100 μmol/L),采用超快速高效液相色谱(UFLC)法测定代谢产物生成速率,以UGT代谢酶残余活性评价抑制能力。从中筛选出抑制能力较强的化合物(半数抑制浓度IC50≤10 μmol/L),对其在人肝微粒体中的抑制机制进行系统研究并计算IC50及抑制常数(Ki)值。IC50值的测定采用单一底物浓度法,在不同浓度代谢酶抑制剂的孵育体系中,代谢产物的生成速率不同,应用非线性回归分析计算而得。Ki的测定需在孵育体系中设计3~4个底物浓度以及4~5个包括0点在内的抑制剂浓度,抑制动力学类型通过Dixon作图法和Lineweaver-Burk作图法确定,采用二次作图法计算Ki结果 山柰酚、槲皮素及甘草查尔酮A对淫羊藿次苷Ⅱ在不同种属肝微粒体及人肠微粒体中的葡萄糖醛酸化反应均具有较强的抑制作用;对在人肝微粒体中的葡萄糖醛酸化反应抑制作用的IC50值分别为(1.01±0.26)、(4.65±0.51)、(5.34±1.00) μmol/L;Dixon作图法及Lineweaver-Burk作图法表明,甘草查尔酮A能够竞争性抑制淫羊藿次苷Ⅱ在人肝微粒体中的葡萄糖醛酸化反应,Ki值为0.18 μmol/L;槲皮素遵循混合型抑制动力学模型,Ki值为0.23 μmol/L;山柰酚符合非竞争型抑制动力学模型,Ki值为0.36 μmol/L。结论 山柰酚、槲皮素及甘草查尔酮A能够降低淫羊藿次苷Ⅱ在不同种属肝微粒体中的葡萄糖醛酸化反应速率,使代谢产物生成减少,清除减慢。  相似文献   

10.
目的 观察和厚朴酚、厚朴酚、栀子苷、绿原酸和黄芪甲苷5种中药成分体外对人和大鼠肝CYP1A2、CYP3A和CYP2D的抑制作用。方法 在人和大鼠肝微粒体孵育体系中,分别以非那西丁、咪达唑仑和右美沙芬为探针,应用HPLC检测受试物对探针代谢产物生成量的影响,评估5种中药成分对CYP1A2、CYP3A和CYP2D在该体系中的活性影响,并计算得到抑制率和IC50。结果 和厚朴酚对人和大鼠CYP1A2、CYP2D的IC50值分别为5.5、3.9、35.3和46.7 μmol·L-1;厚朴酚对人CYP1A2、大鼠CYP1A2和CYP2D的IC50值分别为23.8,29.1和39.9 μmol·L-1;栀子苷、绿原酸和黄芪甲苷对3种CYP酶亚型的IC50均>100 μmol·L-1;和厚朴酚对人和大鼠CYP3A的IC50均>100 μmol·L-1;厚朴酚对人CYP3A、CYP2D和大鼠CYP3A的IC50均>100 μmol·L-1。结论 和厚朴酚体外对人和大鼠CYP1A2和CYP2D有抑制作用,厚朴酚体外对人CYP1A2、大鼠CYP1A2和CYP2D有抑制作用,均呈浓度依赖性。  相似文献   

11.
Both benzo[a]pyrene (BaP) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are potent ligands of aryl hydrocarbon receptors (AhR). Although animal studies indicate that both compounds induce pathological changes in the peripheral lung, the specific cell type involved remains unclear. Clara cells, expressing Clara cell specific protein (CCSP) and abundant in cytochrome P450, are nonciliated bronchiolar epithelial cells in the peripheral lung. Here we explore the hypothesis that CCSP-positive Clara cells are highly responsive to AhR ligands and are the primary cell type involved in BaP- and TCDD-induced toxicities. The responsiveness to AhR ligands was evaluated by measuring the respective mRNA and protein levels of cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1) using real-time RT-PCR and immunocytochemistry assays. Two in vitro models were used: primary cultures of human small airway epithelial (SAE) cells and rat lung slice cultures. In the presence of calcium, human SAE cells differentiated into CCSP-positive cells. BaP- and TCDD-induced mRNA and protein levels of CYP1A1 and CYP1B1 levels were significantly elevated in CCSP-positive cell cultures. Similarly, AhR mRNA and protein levels were increased in CCSP-positive cell cultures, as determined by real-time RT-PCR and Western blot analysis. When rat lung slice cultures were treated with BaP or TCDD for 24 h, CYP1A1 and CYP1B1 proteins were strongly induced in Clara cells. These results indicate that, in the peripheral lung of both rats and humans, CCSP-positive cells (Clara cells) may be more sensitive to AhR ligands than other cell types.  相似文献   

12.
人体存在多种类型的药物转运体,对于药物的吸收、分布和排泄起重要作用。参与药物跨膜转运的转运体功能受影响,将可能导致诸多临床药物的疗效、毒副作用甚至药物相互作用的发生。在各种影响因素中,遗传多态性所起的作用最为重要,可导致基因表达和蛋白功能发生改变。目前,阐明转运体基因的多态性以及基因型与表型之间的相互关系已成为应用遗传信息指导临床个体化用药的必要步骤。本文就肝脏有机阴离子转运多肽1B1(OATP1B1[OATP-C],编码基因SLCO1B1)基因多态性对药代动力学和药效动力学的影响及其临床意义等方面的进展作一综述。  相似文献   

13.
Sulfation of resveratrol, a polyphenolic compound present in grapes and wine with anticancer and cardioprotective activities, was studied in human liver cytosol. In the presence of 3′-phosphoadenosine-5′-phosphosulfate, three metabolites (M1–3) whose structures were identified by mass spectrometry and NMR as trans-resveratrol-3-O-sulfate, trans-resveratrol-4′-O-sulfate, and trans-resveratrol-3-O-4′-O-disulfate, respectively. The kinetics of M1 formation in human liver cytosol exhibited an pattern of substrate inhibition with a Ki of 21.3?±?8.73?µM and a Vmax/Km of 1.63?±?0.41?µL?min?1mg?1 protein. Formation of M2 and M3 showed sigmoidal kinetics with about 56-fold higher Vmax/Km values for M3 than for M2 (2.23?±?0.14 and 0.04?±?0.01?µL?min?1?mg?1). Incubation in the presence of human recombinant sulfotransferases (SULTs) demonstrated that M1 is almost exclusively catalysed by SULT1A1 and only to a minor extent by SULT 1A2, 1A3 and 1E1, whereas M2 is selectively formed by SULT1A2. M3 is mainly catalysed by SULT1A2 and 1A3. In conclusion, the results elucidate the enzymatic pathways of resveratrol in human liver, which must be considered in humans following oral uptake of dietary resveratrol.  相似文献   

14.
Endometriosis is a debilitating disease estimated to affect 10% of reproductive-age women and characterized by the growth of endometrial tissue outside of the uterus. The present study characterizes a human endometrial explant culture model for studying the direct effects of TCDD exposure by assessing the expression of CYP1A1 and CYP1B1 mRNA (Northern blotting), protein (Western blotting), and activity (7-ethoxyresorufin-O-deethylase; EROD) in explants cultured with and without TCDD. Explants were obtained at laparoscopy or laparotomy from women undergoing surgery for tubal ligation, endometriosis, or pelvic pain unrelated to endometriosis. The explants were cultured with 10 nM estradiol (E(2)) or 1 nM E(2) plus 500 nM progesterone (P(4)) with or without TCDD (first 24 h). The expression of CYP1A1 and CYP1B1 mRNA was greatest with 10 nM TCDD and increased up to 72 h after initial exposure. EROD activity increased up to 120 h. Explants from a secretory phase biopsy became reorganized in culture and formed a new epithelial membrane, while maintaining basic endometrial morphology and viability for up to 120 h. At 24 h, TCDD significantly increased CYP1A1 and CYP1B1 mRNA, and at 72 h, TCDD significantly increased EROD activity and CYP1B1 protein compared to explants cultured without TCDD for similar times. CYP1B1 protein also exhibited substantial constitutive expression that was similar in uncultured biopsies, where CYP1B1 protein was immunolocalized in the cytoplasm of epithelial glands, with only occasional patches of protein in the surface epithelial membrane. In explants cultured with and without TCDD exposure, CYP1B1 protein was localized in the cytoplasm of the new surface epithelial membrane and glands closest to the surface. CYP1A1 protein was not detected in uncultured biopsies or explants. Both younger age (age 30 and under) and proliferative phase were associated with higher TCDD-induced EROD activity in specimens treated with E(2):P(4). No significant endometriosis-related differences were observed for any of the biomarkers, but the detection of disease-specific change was limited by small sample size and variability in tissue-cycle phase. The human endometrial explant culture model will be useful for future studies of the effects of dioxin-like compounds on human endometrium in relationship to cycle phase and hormonal exposure.  相似文献   

15.
16.
Human cytochrome P450 1B1 (CYP1B1) is found mainly in extrahepatic tissues and is overexpressed in a variety of human tumors. Metabolic activation of 17β-estradiol (E2) to 4-hydroxy E2 by CYP1B1 has been postulated to be an important factor in mammary carcinogenesis. The inhibition of recombinant human CYP1B1 by 2,2′,4,6′-tetramethoxystilbene (TMS) was investigated using either the Escherichia coli membranes of recombinant human CYP1B1 coexpressed with human NADPH-P450 reductase or using purified enzyme. 2,2′,4,6′-TMS showed potent and selective inhibition of ethoxyresorufin O-deethylation (EROD) activity of CYP1B1 with IC50 values of 2 nM. 2,2′,4,6′-TMS exhibited 175-fold selectivity for CYP1B1 over CYP1A1 (IC50, 350 nM) and 85-fold selectivity for CYP1B1 over CYP1A2 (IC50, 170 nM). However, inhibition of human NADPH-P450 reductase activity by 2,2′,4,6′-TMS was negligible. The modes of inhibition by 2,2′,4,6′-TMS were noncompetitive for CYP1A1 and CYP1B1. Moreover, 2,2′,4,6′-TMS significantly suppressed EROD activity and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced CYP1A1 or CYP1B1 gene expression in human tumor cells such as HepG2 and MCF-10A. Taken together, our results indicate that 2,2′,4,6′-TMS is a potently selective inhibitor of human CYP1B1 as well as a suppressor of CYP1B1 expression and may be a valuable tool for determining enzyme properties of human CYP1B1.  相似文献   

17.
18.
甲型H1N1流感疫苗不良事件监测及评估   总被引:1,自引:0,他引:1  
目的:分析甲型H1N1流感疫苗的接种情况,及时总结接种的监测与评估,为开展甲型H1N1流感防控提供参考。方法:对国内外2009年接种甲型H1N1流感疫苗的不良反应监测报告进行分析。结果:甲型H1N1流感疫苗被认为与季节性流感疫苗总体安全性近似。结论:在甲型H1N1流感大流行的背景下,接种该疫苗利大于弊。  相似文献   

19.
甲流期间469例发热病例血常规分析   总被引:2,自引:0,他引:2  
目的:了解发热病人的血常规特点,做好甲流期间感染性疾病的预诊断。方法:选取我门诊2009年5月~12月期间发热分诊处接诊的病例469例,分析其体温和血常规的关系。结果:血常规分析显示,甲流期间发热患者随着体温逐渐升高,中性粒细胞百分比(NC)增高的比例显著升高,白细胞计数(WBC)和淋巴细胞百分比(LC)变化无统计学意义。结论:甲流期间,发热患者体温越高,细菌感染的趋势越大,而WBC和LC变化无特异性。  相似文献   

20.
New compounds selective for α1A-adrenoceptors in the prostate may offer enhanced efficacy for benign prostatic hyperplasia (BPH), with fewer side effects than current treatment. A-131701 (3-[2-((3aR,9bR)-cis-6-methoxy-2,3,3a,4,5,9b,hexahydro-[1H]-benz[e]isoindol-2-yl)ethyl]pyrido[3′,4′:4,5]thieno [3,2-d]pyrimidine-2,4(1H,3H)-dione), from a novel class of benz[e]isolindole pyridothienopyrimidines and pyridothienopyrazines, is selective for α1a- and α1d-adrenoceptors in radioligand binding studies (0.22 nM at α1a-, 0.97 nM at α1d-) compared to α1b-sites (2.5 nM) and in isolated tissue bioassays (pA2 values of 8.9–9.0 for α1A-receptors in rat vas deferens or canine prostate strips, 9.1 at α1D-sites (rat aorta)), compared to 7.9 at α1B-sites (rat spleen). A-131701 also potently blocked radioligand binding to α1-adrenoceptors in canine and human prostatic membranes, but was considerably weaker at α2-adrenoceptors. In isoflurane-anesthetized dogs, A-131701 antagonized epinephrine-induced increases in intraurethral pressure (IUP) with a pseudo-pA2 value of 8.17. In spontaneously hypertensive rats, A-131701 caused transient decreases in mean arterial blood pressure (MABP) and transient tachycardia. The area under the curve (AUC060 min) for the hypotensive response was dose-related, with a log index value for A-131701 of 5.33, suggesting a selectivity of >600-fold comparing IUP to MABP effects. In pentobarbital-anesthetized dogs, A-131701 was more potent in blocking phenylephrine (PHE)-induced increases in IUP (pseudo-pA2 = 8.0) compared to concurrently measured MABP (pseudo-pA2 = 7.2), or sixfold selective. Doses greater than 1,000 nmol/kg i.v. of A-131701 were required to lower blood pressure by 10 mm Hg in these dogs (pED10 =. 5.57), indicating a uroselectivity ratio of >250, superior to doxazosin, terazosin, or tamsulosin. Thus, A-131701 is selective for α1A- and α1D- vs. α1B-adrenoceptors in vitro, and prostatic function vs. blood pressure effects in vivo, which may provide therapeutic advantages in the treatment of BPH. Drug Dev. Res. 44:140–162, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

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