复方丹参滴丸对大鼠肝微粒体细胞色素P450含量的影响

目的探讨复方丹参滴丸对大鼠肝微粒体细胞色素P450含量的影响。方法利用细胞色素P450在铁蛋白的铁原子被还原与一氧化碳形成复合物时出现一特异性吸收峰，在波长大约450nm处呈现最大吸收，450-490nm波长的消光系数经精确测定为91nm^-1cm^-1，可定量测定细胞色素P450。结果复方丹参滴丸能诱导大鼠肝微粒体细胞色素P450的活性，且其作用随给药时间的延长而增强。结论复方丹参滴丸虽然作为OCT药品，但在长期服用或配伍应用时亦应当慎重。     

复方丹参滴丸对大鼠肝微粒体细胞色素P450含量的影响

目的探讨复方丹参滴丸对大鼠肝微粒体细胞色素P450含量的影响.方法利用细胞色素P450在铁蛋白的铁原子被还原与一氧化碳形成复合物时出现一特异性吸收峰,在波长大约450 nm处呈现最大吸收,450～490 nm波长的消光系数经精确测定为91 nm-1cm-1,可定量测定细胞色素P450.结果复方丹参滴丸能诱导大鼠肝微粒体细胞色素P450的活性,且其作用随给药时间的延长而增强.结论复方丹参滴丸虽然作为OCT药品,但在长期服用或配伍应用时亦应当慎重.     

复方丹参滴丸对大鼠肝微粒体细胞色素P450含量的影响

目的探讨复方丹参滴丸对大鼠肝微粒体细胞色素P450含量的影响。方法利用细胞色素P450在铁蛋白的铁原子被还原与一氧化碳形成复合物时出现一特异性吸收峰,在波长大约450 nm处呈现最大吸收,450~490 nm波长的消光系数经精确测定为91 nm-1cm-1,可定量测定细胞色素P450。结果复方丹参滴丸能诱导大鼠肝微粒体细胞色素P450的活性,且其作用随给药时间的延长而增强。结论复方丹参滴丸虽然作为OCT药品,但在长期服用或配伍应用时亦应当慎重。     

Bay41-4109对大鼠肝脏P450酶系诱导作用的研究*

目的观察Bay41-4109(2-heteroaryl-dihydropyrimidines,HAP,异芳基二氢嘧啶类化合物)诱导处理对大鼠肝细胞色素P450(CYP450)及其主要亚型的影响,并探讨其可能的机制.方法雄性Wistar大鼠分别用Bay41-4109 7.5,30和120mg·kg-1·d-1连续灌胃诱导处理5 d,测定肝脏脏器系数、微粒体总CYP450含量和CYP1A2,2B1/2和3A4亚型活性,并以苯巴比妥为对照.结果经Bay41-4109三个不同剂量诱导后,大鼠肝脏脏器系数、总P450含量、CYP1A2,2B1/2和3A4活性与对照相比均有不同程度升高,并有明确的剂量效应关系,其诱导CYP450代谢酶谱的改变与苯巴比妥基本一致;且Bay41-4109在7.5mg·kg-1·d-1时即对CYP2B1/2和CYP1A2有非常显著的诱导作用,120 mg·kg-1·d-1时引起此两种亚型活性变化大致与苯巴比妥60 mg·kg-1·d-1相当.结论Bay41-4109属于苯巴比妥类的肝药酶强诱导剂,可能通过药物代谢酶系统影响其他药物的代谢.     

地高辛联合氨氯地平对大鼠肝微粒体细胞色素P450的影响

目的研究地高辛合用氨氯地平对大鼠肝脏组织药物代谢酶活性的影响,探讨两药合用后对药物代谢的影响,为临床合理用药提供理论依据。方法雄性大鼠40只,随机均分为空白对照、地高辛、氨氯地平、地高辛+氨氯地平组,每天给药1次,7d后处死。分别测定细胞色素P450和细胞色素b5含量,丙氨酸氨基转移酶、红霉素N-脱甲基酶、氨基比林N-脱甲基酶和7-乙氧基香豆素脱烃酶的活性。结果灌胃给药7d,地高辛、氨氯地平及联合用药对红霉素N-脱甲基酶活性均有明显抑制作用,联合用药的抑制作用未见增强。结论地高辛与氨氯地平合用对细胞色素P450酶系抑制作用未见增强。     

卤酚化合物LM49对大鼠肝微粒体细胞色素P450的影响

目的研究LM49对大鼠肝微粒体蛋白及细胞色素P450含量的影响。方法将大鼠分成空白对照组、溶剂对照组、阳性对照组(苯巴比妥组、地塞米松组、β-萘黄酮组)、LM49低、中、高剂量组。给药后采用超速离心法制备大鼠肝微粒体;BCA法测定大鼠肝微粒体蛋白浓度;Omura and Sato法测定大鼠肝微粒体细胞色素P450的含量。结果 给予不同剂量的LM49后,大鼠肝微粒体的蛋白及细胞色素P450含量均明显降低。低、中、高剂量组与对照组比较差异有统计学意义(P<0.05)。结论 LM49对大鼠肝微粒体细胞色素P450具有一定的抑制作用,可能引起肝药酶对某些药物代谢的改变。     

抗组胺药敏感性的细胞色素P-450在不同年龄组大鼠肝脏微粒体中的测定

抗组胺药敏感性细胞色素P-450(简称HP-450)主要存在于肝脏微粒体,是一个有组胺H₁受体和细胞色素P-450(CytP-450)两种物质特性的蛋白质,我们利用[³H]mepyramine为同位素标记进行受体配体结合实验,检测HP-450随着大鼠增龄而致的动力学特征,同时又从酶学比较Cytp-450在不同年龄组大鼠肝脏微粒体内的变化规律和趋势,发现HP-450和CytP-450都明显地随着大鼠年龄而变化,其中HP-450的Bmax值和Kd值在大鼠出生后2至8周内增加最快,8至10周达到最高水平并趋向稳定状态,CytP-450也有同样的趋势,并且HP-450的增长与CytP-450的增长幅度具有良好的相关性(相关系数r=0.625)。实验中未曾发现性别间的差异。     

地塞米松的诱导效应对环磷酰胺大鼠毒性的影响

目的:观察地塞米松(dexamethasone,DEx)对大鼠细胞色素P450的诱导效应致环磷酰胺(cyclophos-phamide,CPA)对肝脏、肾脏、骨髓和膀胱毒性的影响.方法:雄性Wistar大鼠用DEX 50mg·kg-1·d-1诱导4d后,d5分别ip CPA 0,150和200mg·kg-1后36h,观察实验动物肝脏、肾脏、骨髓和膀胱毒性表现.结果:单独DEX诱导具有轻微的肝脏毒性.CPA单次给药造成骨髓细胞G2M期细胞的比例稍有升高,出现明显的尿蛋白和尿潜血.DEX的诱导作用增加了CPA的毒性:对肝毒性的增强作用主要表现在血浆ALT升高,肝脏总巯基和蛋白巯基含量降低,肝脏组织肝窦狭窄,肝小叶空泡变性;对肾脏毒性增强表现在血浆BUN和Cr升高,尿液蛋白和潜血增加,肾近端小管变性和髓质出血.DEX和CPA 200mg·kg-1合并用药组骨髓细胞的G0/G1期细胞增多,S期细胞明显减少.病理检查表明DEX和CPA合并用药组膀胱发生炎症和出血.结论:DEX诱导后使CPA对大鼠的肾脏、膀胱和骨髓毒性进一步增强,而DEX具有一定的肝脏毒性,与CPA合并给药后肝毒性有增强趋势.     

复方毛冬青颗粒对大鼠肝微粒体细胞色素P450酶的诱导作用研究

目的研究复方毛冬青颗粒对大鼠细胞色素P450酶的诱导作用。方法复方毛冬青颗粒0.5、2.0、6.0g·kg-1·d-13个剂量组,雄性SD大鼠连续灌胃7d,取肝脏组织,制备肝微粒体,应用"cocktail"方法检测CYP450酶活性的变化。结果复方毛冬青颗粒能明显的诱导大鼠肝脏CYP1A2和CYP2E1的活性,且呈剂量依赖性:0.5、2.0、6.0g·kg-1·d-13个剂量组同空白对照组比,使CYP1A2的活性分别增加了55.9%,93.4%,176.4%,使CYP2E1的活性分别增加了16.1%,60.4%,111.3%,而对其他亚型没有影响。结论丹参酮ⅡA对大鼠CYP1A2和CYP2E1亚型有诱导作用,提示可能导致药物相互作用。     

Effects of flupyrazofos on liver microsomal cytochrome P450 in the male Fischer 344 rat

1. The effects of flupyrazofos on liver microsomal cytochrome P450 were investigated in the male Fischer 344 rat. When rats were treated intraperitoneally with flupyrazofos for 3 consecutive days, the activities of ethoxyresorufin O-deethylase and testosterone 2 beta-hydroxylase were significantly reduced, whereas the activities of pentoxyresorufin beta-depentylase and testosterone 6beta- and 7 alpha-hydroxylases were induced in liver microsomes. 2. Within 24 h after treatment with 50 m kg(-1) flupyrazofos, most enzyme activities were decreased, indicating the interaction of flupyrazofos with cytochrome P450. 3. In Western immunoblotting, cytochrome P4502B1/2 proteins were clearly induced by treatment with flupyrazofos, whereas P4501A1/2 and 2C6 proteins were reduced in liver microsomes. 4. The present results indicate that flupyrazofos modulates the expression of cytochrome P450 in rat.     

淫羊藿苷对不同月龄大鼠肝微粒体细胞色素P450的影响

目的 揭示淫羊藿苷(Ica)对大鼠肝微粒体细胞色素P450的含量及部分亚型的影响,并比较月龄的差异.方法 ig给予6月龄和18月龄的♂SD大鼠Ica( 60 mg· kg -1),4周后取肝脏,用钙沉淀法提取肝微粒体,BCA法测定微粒体蛋白浓度;用一氧化碳还原差示光谱法测定CYP450的含量;用ELISA法测定CYP1 A1、CYPb5的含量;用比色法测定苯胺羟化酶(反映CYP2E1活性)和红霉素-N-脱甲基酶(反映CYP3A活性)的活性;用real - time RT - PCR检测CYP1 A1、CYP2A3、CYP2E1、CYP3A1、CYP3A2和CYP4B1 mRNA的表达.结果 60 mg· kg-1 Ica明显增加了CYP450的总酶和CYP1 A1的含量、CYP3A的活性及CYP1 A1、CYP3A1、CYP3A2 mRNA的表达,降低了CYP2E1的活性及其mRNA的表达;但Ica对上述各指标的诱导或抑制作用在大鼠月龄方面差异不明显;Ica对CYPb5的含量及CYP2A3、CYP4B1 mRNA的表达未见明显影响.结论 Ica对大鼠肝微粒体CYP450总酶、CYPI A1和CYP3A具有诱导作用,对CYP2E1具有抑制作用,该作用未见明显月龄差异.     

Effects of flupyrazofos on liver microsomal cytochrome P450 in the male Fischer 344 rat

1. The effects of flupyrazofos on liver microsomal cytochrome P450 were investigated in the male Fischer 344 rat.When rats were treated intraperitoneally with flupyrazofos for 3 consecutive days, the activities of ethoxyresorufin O-deethylase and testosterone 2 β-hydroxylase were significantly reduced, whereas the activities of pentoxyresorufin O-depentylase and testosterone 6 β- and 7 α-hydroxylases were induced in liver microsomes. 2. Within 24 h after treatment with 50 m kg^?1 flupyrazofos, most enzyme activities were decreased, indicating the interaction of flupyrazofos with cytochrome P450. 3. In Western immunoblotting, cytochrome P4502B1/2 proteins were clearly induced by treatment with flupyrazofos, whereas P4501A1/2 and 2C6 proteins were reduced in liver microsomes. 4. The present results indicate that flupyrazofos modulates the expression of cytochrome P450 in rat.     

Effects of photoisomers of cyclodiene insecticides on liver and microsomal cytochrome P450 in rats

Threshold dosages of the photoisomers of cyclodiene insecticides, namely photochlordane, photodieldrin, and photoheptachlor, for the induction of hepatic microsomal cytochrome P450 (P450) and liver hypertrophy in male rats were at least one-quarter of those reported for corresponding parent cyclodienes. Maximum increase in total P450 concentration (30%) and demethylases activities (100%) was always respectively one-third or one-tenth of that reported for parent cyclodienes. The P450 isozymic form induced by photoheptachlor resembled that induced by pentobarbital (P4502B1) in its substrate specificity, spectral characteristics, and electrophoretic mobility. The induction of P450 was initially followed by hepatic hypertrophy. However, higher dosages of photoisomers caused wasting and lowered both the liver weight and the activity of aniline hydroxylase while those of mirex and endrin, which also caused wasting and lowered aniline hydroxylase activity, continued causing further hepatic hypertrophy.     

慢性间断性低氧对大鼠肝脏细胞色素P450的影响

目的观察慢性间断性低氧对大鼠肝脏P450同工酶的影响。方法♂SD大鼠随机分为对照组和实验组,实验组分别低氧3、7、14、28d。采用酶法测定血清丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)活性,分光光度法测定大鼠肝微粒体红霉素N-脱甲基酶(ERD)、苯胺羟化酶(ANH)活性,半定量逆转录聚合酶链式反应(RT-PCR)检测大鼠肝脏细胞色素P4503A2、2E1的mRNA表达水平。结果慢性间断性低氧对血清ALT和AST活性无明显影响;低氧7d后,大鼠肝脏ERD和ANH活性明显升高,28d时诱导率分别为155·5%和42·2%;同时CYP3A2和CYP2E1mR-NA的表达水平,也分别增加了220·5%和102·8%。结论慢性间断性低氧能明显增加大鼠肝脏ERD(CYP3A2)和ANH(CYP2E1)活性,其机制可能与其在转录水平上提高肝脏CYP3A2和CYP2E1的基因表达水平有关。     

灯盏细辛注射液对小鼠肝微粒体细胞色素P450含量的影响

目的:研究灯盏细辛注射液对小鼠肝微粒体细胞色素P450含量的影响。方法:小鼠分为空白对照组、阳性对照组(苯巴比妥钠80mg/kg,i.p.,共7d)、灯盏细辛注射液正常剂量组、高剂量组(10、30mg/kg,i.p.,共14d)。用紫外分光光度法测定细胞色素P450及其同工酶的活性。结果:灯盏细辛注射液两剂量组小鼠肝微粒体的蛋白含量和细胞色素P450含量较空白对照组增高,对肝重指数基本无影响;可抑制红霉素-N-脱甲基酶(ERD)的活性(P<0.01),而对氨基比林-N-脱甲基酶(AMD)基本无影响(P>0.05);苯巴比妥钠组肝重指数、蛋白含量和细胞色素P450含量与其他各组比较均升高(P<0.05),对氨基比林-N-脱甲基酶、红霉素-N-脱甲基酶活性均有诱导作用(P<0.01)。结论:灯盏细辛注射液对小鼠肝微粒体蛋白、细胞色素P450含量有一定影响,对CYP3A可能有抑制作用,对氨基比林-N-脱甲基酶活性基本无影响。     

甘草水煎液对大鼠肝微粒体细胞色素P450酶活性的影响

目的：观察甘草水煎液对大鼠肝细胞色素P450酶活性的影响。方法：SD大鼠随机分为4组,分别为空白对照组（给予生理盐水）、酶诱导剂组（给予苯巴比妥）、酶抑制剂组（给予西咪替丁）及甘草水煎液组（给予甘草水煎液）,各组动物连续灌胃给药14 d,第15天腹腔注射探针药物非那西丁,不同时间点采集血样后,HPLC法测定血浆中非那西丁浓度,并估算其药代动力学参数。结果：生理盐水组、苯巴比妥组、西咪替丁组及甘草水煎液组非那西丁的t1/2分别为（104±10）、（178±15）、（86±9）、（90±9）min。结论：甘草水煎液对大鼠肝药酶P450具有一定的诱导作用。     

六味地黄丸对大鼠肝微粒体代谢酶P450活性的影响

目的:考察六味地黄丸对大鼠肝微粒体代谢酶P450活性的影响.方法:大鼠灌胃分别给予生理盐水、西咪替丁、苯巴比妥钠和六味地黄丸7 d后,腹腔注射非那西丁,不同时间点采集血样,用HPLC法测定血浆中探针药物非那西丁的浓度,用DAS软件估算其药动学参数.结果:生理盐水组、西咪替丁组、苯巴比妥钠组和六味地黄丸组探针药物的t1/2分别为(93.5±9.2),(161.7±11.0),(85.4±9.0),(67.0±6.7)min.结论:六味地黄丸对大鼠肝微粒体代谢酶P450活性有一定的诱导作用.     

Differential induction of cytochrome P450 isoforms and peroxisomal proliferation by cyfluthrin in male Wistar rats

Cyfluthrin effects on in vivo drug metabolizing enzymes were evaluated using the oxidative substrate antipyrine. Antipyrine pharmacokinetics in plasma and urinary excretion of its major metabolites with and without cyfluthrin oral treatment (20 mg/kg/day for 6 days) were investigated in rats. Cyfluthrin increased the apparent intrinsic clearance and decreased the antipyrine half-life at β phase. Cyfluthrin also increased the clearance of the antipyrine metabolites, norantipyrine, 4-hydroxyantipyrine and 3-hydroxymethylantipyrine and the formation rate constants for each of the three metabolites measured in urine. These results suggest that cyfluthrin affects hepatic cytochrome P450 (CYP) system. In order to confirm, a second experiment was carried out. We evaluated the effects of repeated exposure to cyfluthrin on hepatic and renal CYP2E, CYP1A and CYP4A subfamilies and peroxisomal proliferation in rats following oral administration (10 and 20 mg/kg/day for 6 days). At the highest dose, cyfluthrin increased renal and hepatic O-deethylation of ethoxyresorufin and O-demethylation of methoxyresorufin, metabolism mediated by the CYP1A subfamily. Liver and kidney were susceptible to cyfluthrin-dependent induction of 12- and 11-hydroxylation of lauric acid, suggesting CYP4A subfamily induction. Also cyfluthrin increased the β-oxidation of palmitoyl-coenzyme A and carnitine acetyltransferase activity, supporting cyfluthrin as a peroxisome proliferator. In conclusion, the demonstration that cyfluthrin induced hepatic CYP1A, CYP4A subfamilies and peroxisomal proliferation raises the possibility of cyfluthrin could produce changes in oxidative stress.