Effects of huperzine A on secretion of nerve growth factor in cultured rat cortical astrocytes and neurite outgrowth in rat PC12 cells

Aim: To study the effects of huperzine A (HupA) on neuritogenic activity and the expression of nerve growth factor (NGF). Methods: After being treated with 10μmol/L HupA, neurite outgrowth of PC 12 cells was observed and counted under phase-contrast microscopy. Mitogenic activity was assayed by [^3H]thymidine incorporation. Cell cytotoxicity was evaluated by lactate dehydrogenase (LDH) release. AChE activity, mRNA and protein expression were measured by the Ellman‘s method, RT-PCR, and Western blot, respectively. NGF mRNA and protein levels were determined by RT-PCR and ELISA assays. Results: Treatment of PC 12 cells with 10μmol/L HupA for 48 h markedly increased the number of neuritebearing cells, but caused no significant alteration in cell viability or other signs of cytotoxicity. In addition to inhibiting AChE activity, 10μmol/L HupA also increased the mRNA and protein levels of this enzyme. In addition, following 2h exposure of the astrocytes to 10μmol/L HupA, there was a significant up-regulation of mRNA for NGF and P75 low-affinity NGF receptor. The protein level of NGF was also increased after 24 h treatment with HupA. Conclusion: Our findings demonstrate for the first time that HupA has a direct or indirect neurotrophic activity, which might be beneficial in treatment of neurodegenerative disorders such as Alzheimer disease.     

Effect of γ-ray on metabolic enzyme CYP3A1 in rat liver on multiple levels北大核心CSCD

Aim To explore the effect of γ-ray on the mRNA,protein expression levels and metabolic activity level of the key drug metabolic enzyme CYP3A1 in rat liver. Methods Wistar rats were randomly divided into control group, 24 h post-radiation group and 72 h post-radiation group. The experimental group was exposed to total body irradiation of single 6 Gy γ-ray. Blood was collected from the orbital venous plexus for blood routine examination and biochemical analysis 24 h and 72 h after irradiation, and liver tissue was prepared for quantifying expression of CYP3A1 mRNA and liver-specific microRNA (miR-122-5p) through RT-PCR. The expression level of CYP3A1 protein was analyzed by Western blot, and the metabolic activity level of CYP3A1 detected by the specific substrate midazolam combined with LC-MS method. Results Com¬pared with the control group, the weights of the rats in the radiation group significantly decreased, and the number of white blood cells was markedly reduced. Simultaneously, the activities of alanine aminotrans-ferase and alkaline phosphatase continuously descended, as well as the levels of total bilirubin and bile acid significantly increased, which indicated that the liver may be damaged after radiation. The relative expression of CYP3A1 mRNA continued to increase significantly 24 h and 72 h after irradiation. CYP3A1 protein expression and metabolic activity levels showed an obvious increasing trend 24 h after irradiation, and rose significantly 72 h after irradiation compared with the control group. At the same time, the expression of miR-122-5p in liver of rats in the 24 h and 72 h post-radiation group continued to decrease rapidly compared with the control group. Conclusions γ-ray radiation may arouse damage effect on liver, which leads to the continuous up-regulation of the mRNA and protein expression levels of the capital metabolic enzyme CYP3A1 in liver tissue, as well as the elevation of the metabolic activity level. The regulatory mechanism might be related to miR-122-5p. © 2023 Publication Centre of Anhui Medical University. All rights reserved.     

Inhibitory effect of tea polyphenals on transforming growth factor-β1 expression in rat with cyclosporine A-induced chronic nephrotoxicity

AIM: To investigate the inhibitory effect of tea polyphenols (TP)on the transforming growth factor-pi (TGF-β1) expression in rat model of cyclosporine A (CsA)-induced chronic nephrotoxicity. METHODS: The rat model of CsA-induced chronic nephrotoxicity was used, 4 groups of rats were respectively treated with vehicle (0.1 mL·lg-1-d-1 sc), TP (80 mg·kg-1·d-1 ig), CsA (15 mg·2kg-1·d-1sc) and TP plus CsA (CsA 15 mg·kg-1·d-1 sc TP 80 mg·kg-1·d-1 ig). At the end of day 28 of treatment, serum and urine are analyzed for creatinine clearance, kidney tissue for pathologic analysis. The TGF-β1 mRNA and its protein expression were detected by RT-PCR, immunohistochemistry, and Western blot. RESULTS: CsA-treated rats had increased renal expression of TGF-pl mRNA and its protein, compared with the vehicle- or TP- treated     

Osteogenic effects of D（＋）β-3,4-dihydroxyphenyl lactic acid （salvianic acid A,SAA） on osteoblasts and bone marrow stromal cells of intact and prednisone-treated rats

Aim： Previous studies have shown that D（＋）β-3,4-dihydroxyphenyl lactic acid （salvianic acid A, SAA） has anabolic effects on prednisone （GC）-induced osteoporosis in rats. The current study aims to investigate the molecular mechanism of SAA＇s impact on osteogenesis and adipogenesis in bone marrow stromal cells in intact and GC-treated rats.
Methods： For in vitro study, newborn rat calvaria osteoblasts （rOBs） and rat bone marrow stromal cells （rMSCs） were isolated, identified and cultured with SAA at different concentrations to evaluate SAA＇s influence on osteogenesis and adipogenesis. In addition, 3-month-old Sprague-Dawley （SD） male rats were treated with distilled water, prednisone alone （3.0 mg·kg^-1·d^-1） or prednisone （3.0 mg·kg^-1·d^-1） and SAA （25 mg·kg^-1·d^-1） for 45 d. At the end point, the different groups of rMSCs were isolated by density-gradient centrifugation and cultured.
Results： （1） At 0.1-10.0 mg/L, SAA increased ALP activity, type I collagen （Coil-I） mRNA and OPG mRNA expression and stimulated nodule mineralization of rOBs. SAA （0.5 mg/L） also significantly increased the ALP activity of rMSCs without a need for osteogenesis-inducing medium. At 5.0 mg/L, SAA decreased the number of adipocytes with less lipid droplet formation from the rMSCs, which typically undergo adipocyte induction. （2） Coll-I expression was markedly decreased, whereas lipoprotein lipase （LPL） mRNA expression increased by 98% when compared with the first generation of rMSCs in GC-treated rats. The SAA-treated rats demonstrated an over 2-fold increase in Coll-I expression when compared with intact rats and further showed a significant decrease in LPL expression when compared with GC-treated rats. When rMSCs were co-cultured with SAA （0.5 mg/L） in vitro, SAA did not affect Coll-I and LPL gene expression in intact rats but significantly increased ColM and decreased LPL gene expression in GC-treated rats.
Conclusion： SAA protected bone from GC-i     

Dopamine D1 receptor activation induces dehydroepiandrosterone sulfotransferase （SULT2A1） in HepG2 cells

Aim： Dopamine receptors are present in the nervous system and also widely distributed in the periphery. The aim of this study was to investigate the role of D1 subtype dopamine receptors （DRD1） in the regulation of dehydroepiandrosterone sulfotransferase （SULT2A1） in HepG2 cells. Methods： HepG2 cells were treated with DRD1 agonists with or without DRD1 antagonist for 9 d. DRD1 and SULT2A1 mRNA expression, protein expression, and SULT2A1 activity were detected using RT-PCR, Western blotting and HPLC, respectively. The level of cAMP was measured using a commercial kit. Results： All the 5 DR subtypes （DRD1-DRD1） were found to be expressed in HepG2 cells. Treatment of HepG2 cells with the specific DRD1 agonists SKF82958 （2.5 μmol/L） or SKF38393 （5 and 50 μmol/L） significantly increased the mRNA and protein expression of both DRD1 and SULT2A1, and increased SULT2A1 activity and cAMP levels. These effects were partially blocked by co-treatment with the specific DRD1 antagonist SCH23390 （2.5 μmol/L）. In addition, transfection of HepG2 cells with DRD1-specific siRNAs decreased DRD1 mRNA expression by 40%, which resulted in the reduction of SULT2A1 mRNA expression by 60%, protein expression by 40%, and enzyme activity by 20%. Conclusion： DRD1 activation upregulates DRD1 and SULT2A1 expression and SULT2A1 activity in HepG2 cells, suggesting that the DRD1 subtype may be involved in the metabolism of drugs and xenobiotics through regulating SULT2A1.     

Altered expression of cytochrome P450 and possible correlation with preneoplastic changes in early stage of rat hepatocarcinogenesis

Aim: Correlation of cytochrome P450 (CYPs) with preneoplastic changes in the early stage of hepatocarcinogenesis is still unclear. To detect the expression of carcinogen-metabolizing related microsomal P450 enzymes, namely the CYP1A1,CYP1A2, CYP2B 1/2, CYP2E1, and CYP3A, we performed the medium-term bioassay of Ito‘s model in Sprague-Dawley rats. Methods: The amount and activity of CYP were assessed by biochemical and immunohistochemical methods in week 8.The correlation between CYP expression and microsomal oxidative stress was investigated by comparing the generation of microsomal lipid peroxidation in the presence or absence of specific CYP inhibitor. Results: In the DEN-2-AAF and 2-AAF alone groups, the expression of CYP1A1 and CYP2E1 were up-regulated and the expression of CYP2B 1/2 and CYP1 A2 were quite the contrary. Strong staining of CYP2E1 and CYP2BI/2 was found around the centrolobular vein and weak staining in the altered hepatic foci revealed by immunohistochemical procedure.There was no significant change in the activity of CYP3A among the 4 groups.Altered hepatic tissue bore more microsomal NADPH (nicotinamide adenine dimucleotide phosphate,reduced form)-dependent lipid peroxidation than normal tissue. And the difference among the 4 groups disappeared when CYP2E1 was inhibited. More microsomal lipid peroxidation was generated when incubated with CYP1A inhibitor α-naphthoflavone. Conclusion: CYP altered their expression levels and these alterations can play important roles in the alteration of cell redox status of preneoplastic tissue in the early stage of hepatocarcinogenesis.     

Protective effects of bendazac lysine on early experimental diabetic nephropathy in rats

Aim: To investigate the preventive and protective effects of bendazac lysine (BDL) on experimental early diabetic nephropathy (DN) rats. Methods: After an early DN model was induced by streptozotocin, rats were administered BDL at doses of 100, 200, and 400 mg/kg for 8 weeks. Blood glucose, microalbuminuria,kidney index, total antioxidative capacity, laminin, advanced glycation end products (AGE), aldose reductase (AR) activity, and the relative quantity of transforming growth factor β1 (TGF-β1) mRNA were measured by different methods.The ultrastructural morphology was observed by transmission electron microscope. Results: The physical behaviors of early DN rats were hypopraxia,cachexia, and polyuria, while those treated with high doses of BDL were vibrant and vigorous. For BDL-treated DN rats, when compared with vehicle-treated DN rats, the blood glucose level and the intensity of oxidative stress were ameliorated.Also, the microalbuminuria level, AGE either in serum or in renal, and AR activity were significantly reduced. Furthermore, the expression of TGF-β1 mRNA in the kidney cortex was declined and the thickness of glomerular base membrane was decreased significantly. The ultrastructure of glomerulus and mesangial matrix of BDL-treated DN rats were ameliorated. Conclusion: BDL has protective effects on several pharmacological targets in the progress of DN and is a potential drug for the prevention of early DN.     

Pioglitazone can ameliorate insulin resistance in low-dose streptozotocin and high sucrose-fat diet induced obese rats

Aim: To investigate the effect of the peroxisome proliferator-activator receptor (PPAR)-γ agonist, pioglitazone, on insulin resistance in low-dose streptozotocin and high sucrose-fat diet induced obese rats. Methods: Normal female Wistar rats were injected intraperitoneally with low-dose streptozotocin (STZ, 30mg/kg) and fed with a high sucrose-fat diet for 8 weeks. Pioglitazone (20mg/kg) was administered orally to the obese and insulin-resistant rats for 28d. Intraperitoneal glucose tolerance tests, insulin tolerance tests and gluconeogenesis tests were car ried out over the last 14d. At the end of d 28 of the treatment, serums were collected for biochemical analysis. Glucose transporter 4 (GLUT4) and insulin receptor substrate-1 (IRS-1) protein expression in the liver and skeletal muscle were detected using Western blotting. Results: Significant insulin resistance and obesity were observed in low-dose STZ and high sucrose-fat diet induced obese rats. Pioglitazone (20mg/kg) treatment significantly decreased serum insulin,triglyceride and free fatty acid levels, and elevated high density lipoprotein-cholesterol (HDL-C) levels. Pioglitazone also lowered the lipid contents in the liver and muscles of rats undergoing treatment. Gluconeogenesis was inhibited and insulin sensitivity was improved markedly. The IRS-1 protein contents in the liver and skeletal muscles and the GLUT4 contents in skeletal muscle were elevated significantly. Conclusion: The data suggest that treatment with pioglitazone improves insulin sensitivity in low-dose STZ and high sucrose-fat diet induced obese rats. The insulin sensitizing effect may be associated with ameliorating lipid metabolism, reducing hyperinsulinemia, inhibiting gluconeogenesis, and increasing IRS-1 and GLUT4 protein expression in insulin-sensitive tissues.     

Atorvastatin prevents amyloid-13 peptide oligomer- induced synaptotoxicity and memory dysfunction in rats through a p38 MAPK-dependent pathway

Aim： To investigate whether atorvastatin treatment could prevent Aβ1-42 oligomer （AβO）-induced synaptotoxicity and memory dysfunction in rats, and to elucidate the mechanisms involved in the neuroprotective actions of atorvastatin.
Methods： SD rats were injected with AβOs （5 nmol, icv）. The rats were administrated with atorvastatin （10 mg·kg^-1·d^-1, po） for 2 consecutive weeks （the first dose was given 5 d before AβOs injection）. The memory impairments were evaluated with Morris water maze task. The expression of inflammatory cytokines in the hippocampus was determined using ELISA assays. The levels of PSD-95 and p38MAPK proteins in rat hippocampus were evaluated using Western blot analysis. For in vitro experiments, cultured rat hippocampal neurons were treated with AβOs （50 nmol/L） for 48 h. The expression of MAP-2 and synaptophysin in the neurons was detected with immunofluorescence.
Results： The AβO-treated rats displayed severe memory impairments in Morris water maze tests, and markedly reduced levels of synaptic proteins synaptophysin and PSD-95, increased levels of inflammatory cytokines （IL-1β, IL-6 and TNF-α） and p38MAPK activation in the hippocampus. All these effects were prevented or substantially attenuated by atorvastatin administration. Pretreatment of cultured hippocampal neurons with atorvastatin （1 and 5 μmol/L） concentration-dependently attenuated the AβO-induced synaptotoxicity, including the loss of dendritic marker MAP-2, and synaptic proteins synaptophysin and PSD-95. Pretreatment of the cultured hippocampal neurons with the p38MAPK inhibitor SB203580 （5 μmol/L） blocked the AβO-induced loss of synaptophysin and PSD-95.
Conclusion： Atorvastatin prevents AβO-induced synaptotoxicity and memory dysfunction through a p38MAPK-dependent pathway.     

Hypoglycemic effect of Astragalus polysaccharide and its effect on PTP1B

Aim: To examine the effects ofAstragalus polysaccharide (APS), a component of an aqueous extract ofAstragalus membranaceus roots, on protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin-receptor (IR) signal transduction, and its potential role in the amelioration of insulin resistance. Methods: Ten-week-old fat-fed streptozotocin (STZ)-treated rats, an animal model of type Ⅱ diabetes mellitus (TIIDM), were treated with APS (400 mg/kg po) for 5 weeks. Insulin sensitivity was identified by the insulin-tolerance test. Further analyses on the possible changes in insulin signaling occurring in skeletal muscle and liver were performed by immunoprecipitation or Western blotting. PTP1B activity was measured by an assay kit. Results: The diabetic rats responded to APS with a significant decrease in body weight, plasma glucose, and improved insulin sensitivity. The activity and expression of PTP1B were elevated in the skeletal muscle and liver of TIIDM rats. Thus the insulin signaling in target tissues was diminished. APS reduced both PTP1B protein level and activity in the muscle, but not in the liver of TIIDM rats. Insulin-induced tyrosine phosphorylation of the IR β-subunit and insulin receptor substrate-1 (IRS-1) were increased in the muscle, but not in the liver of APS-treated TIIDM rats. There was no change in the activity or expression of PTP1B in APS-treated normal rats, and blood insulin levels did not change in TIIDM rats after treatment with APS. Conclusion: APS enables insulin-sensitizing and hypoglycemic activity at least in part by decreasing the elevated expression and activity of PTP1B in the skeletal muscles of TIIDM rats.     

地非三唑对大鼠肝细胞细胞色素P450 CYP1A1/2的诱导作用

目的 试从mRNA表达水平阐明地非三唑对鼠肝微粒体中细胞色素P450 CYP1A1/2的诱导机制。方法 给SD大鼠腹腔注射地非三唑，采用Trizol法提取大鼠肝脏RNA,用RT-PCR测定经地非三唑处理1, 2及4 d的鼠肝中细胞色素P450 CYP1A1, CYP1A2 mRNA的表达水平。结果 地非三唑处理不同时间的鼠肝细胞中细胞色素P450 CYP1A1, CYP1A2 mRNA的表达水平比空白对照组明显增加，空白对照组CYP1A1吸光度比值为0.270±0.040, 诱导1, 2及4 d的吸光度比值分别为0.343±0.055, 0.417±0.045及0.603±0.083；空白对照组的CYP1A2吸光度比值为0.613±0.189, 而诱导1，2及4 d的吸光度比值分别为1.510±0.226, 3.057±0.518及4.120±0.458。随着诱导时间的增加，细胞色素P450 CYP1A1及CYP1A2 mRNA的表达也逐步增加，诱导时间与表达水平之间存在一定的线性关系,相关系数分别为0.9984和0.9563。结论 地非三唑对细胞色素P450 CYP1A1/2 mRNA表达具有诱导作用。     

石杉碱甲改善老年大鼠水迷宫操作记忆障碍(英文)

目的:测试石杉碱甲对自然衰老及东莨菪碱导致的空间记忆缺损的作用。方法:采用大鼠的水迷宫操作,检测石杉碱甲对获得及记忆的作用。结果:连续7天获得试验期间,皮下注射石杉碱甲0.1-0.2mg/kg能明显缩短老年大鼠找到平台的潜伏期。在第8天撤去平台的记忆测试,石杉碱甲0.1,0.2与0.4 mg/kg明显延长老年大鼠在该平台区的游泳时间。单次腹腔注射东莨菪碱0.1mg/kg明显损害已训练达标老年大鼠的空间记忆。皮下注射石杉碱甲0.4 mg/kg明显翻转东莨菪碱产生的记忆损害作用。结论:石杉碱甲能改善老年大鼠自然衰老或东莨菪碱产生的记忆障碍。     

CYP2E1 mediated isoniazid-induced hepatotoxicity in rats

INTRODUCTIONIsoniazid (INH) in the treatment of all types oftuberculosis (TB) is associated with mild to moderateelevation of liver enzyme activity in plasma, and severehepatotoxicity in approximate 1 %-2 % of patients. Acetyl-hydrazine, the metabolite of INH, has been suggested tobe the cause of hepatic damage in patients. Recently,hydrazine, not INH or acetylhydrazine, has been reportedto be most likely involved in the pathogenic mechanismof hepatic necrosis of INH-induced hepatot…     

心肌缺血再灌注损伤对大鼠肝细胞色素P450酶代谢的影响

目的探讨心肌缺血再灌注状态下,大鼠肝代谢功能和相关的氧化/抗氧化能力变化。方法雄性SD大鼠随机分为5组,除假手术组外,制备在体心肌缺血再灌注模型,并于缺血40min、再灌注15,60和180min分别处死大鼠,检测血浆丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)活性,肝匀浆丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性;以红霉素N-脱甲基酶、五氧基异噁唑O-脱乙基酶和苯胺羟化酶法为探针测定肝细胞色素P450(CYP)3A,CYP2B1和CYP2E1催化功能;RT-PCR法检测肝Ⅰ相药物代谢酶CYP3A1,CYP2B1/2,CYP2E1,以及Ⅱ相解毒酶NAD(P)H醌氧化还原酶(NQO1)及其上游因子NF-E2相关因子(Nrf2)mRNA水平。结果再灌注60 min,肝匀浆MDA含量升高(P<0.05),SOD活力下降(P<0.01);再灌注180 min时,血浆ALT和AST活性升高(P<0.05)。Nrf2基因于再灌注60 min时显著激活(P<0.05),下游因子NQO1 mRNA于再灌注180 min时明显上调(P<0.05)。CYP3A催化功能和mRNA水平分别于再灌注60和180 min开始明显降低(P<0.05);CYP2B1/2 mRNA和催化功能水平分别于再灌注15和180 min开始明显降低(P<0.05);CYP2E1催化功能无明显改变。结论大鼠心肌缺血再灌注可引起肝组织氧化应激及并导致功能损伤。在再灌注早期,具有抗氧化功能的NQO1在转录水平显著上调,其机制可能与上游因子Nrf2被激活相关;CYP3A和CYP2B催化功能在转录和(或)转录后水平明显下调。     

中国汉族人群中CYP3AP1基因型与CYP3A活性的相关性研究

目的:研究中国汉族人群中CYP3AP1基因型的分布特征及其与CYP3A活性的相关性.方法:以口服7.5mg咪哒唑仑后1小时血浆中1′-羟化咪哒唑仑与咪哒唑仑的比值作为CYP3A活性的衡量指标,测定191名中国汉族健康受试者的CYP3A活性,并利用多聚酶链式反应-限制性片段长度多态性(PCR-RFLP)方法对已知CYR3A活性受试者的DNA进行CYP3AP1基因分型.结果:CYP3AP1不同基因型个体的CYR3A活性存在显著差异(P<0.05).A_(-44)等位基因纯合子个体的CYP3A活性低于A_(-44)G杂合子,而G_(44)等位基因纯合子个体的CYP3A活性最高.结论:CYP3AP1基因型与体内CYP3A活性的增加存在相关性.     

Cocktail法研究脉络宁注射液对大鼠CYP1A2、CYP2E1和CYP3A4活性的影响

目的：研究脉络宁注射液对大鼠CYP1A2、CYP2E1和CYP3A4活性的影响。方法：14只大鼠随机均分成临床等效剂量组和高剂量组,连续2周静脉给予脉络宁注射液（临床等效剂量纽,2mL／kg;高剂量组,4mL／kg）前后,均同时灌胃给予3个探针底物（茶碱,30mg／kg;氯唑沙宗,50rag／kg;氨苯砜,20mg/kg）,进行采血试验。用HPLC法同时测定大鼠体内各探针的血药浓度,DAS1．0软件计算药动学参数,并以配对t检验对各组大鼠前后两轮主要药动学参数进行差异性比较。结果：在1个给药疗程（14d）内,临床等效剂量组大鼠用药前后,3个探针的药动学参数均无显著性变化（P〉0．05）;高剂量组大鼠用药后,与用药前相比,茶碱的药动学参数没有显著变化（P〉0．05）;氨苯砜和氯唑沙宗的AUC0-24h均有升高趋势（P〈0．05）,给药后分别是给药前的1．44倍和1．28倍,同时氯唑沙宗的CL显著降低（P〈0．05）。结论：临床等效剂量脉络宁对大鼠CYP1A2、CYP2E1和CYP3A4活性均无显著影响,而高剂量脉络宁对大鼠CYP2E1和CYP3A4均有弱抑制作用。     

Huperzine A ameliorates the impaired memory of aged rat in the Morris water maze performance

AIM: To determine the memory-improving properties of huperzine A in aged rats with memory impairments naturally occurring or induced by scopolamine. METHODS: Morris water maze was used to investigate the effects of huperzine A on the acquisition and memory impairments. RESULTS: During 7-day acquisition trials, aged rats took longer latency to find the platform. Huperzine A (0.1-0.2 mg/kg, s.c.) could significantly reduce the latency. In the probe trials on the eighth day, huperzine A (0.1, 0.2 and 0.4 mg/kg, s.c.) significantly increased the time in the quadrant where plateform had disappeared in aged rats. In the acute experiment, scopolamine (0.1 mg/kg, i.p.) significantly impaired spatial memory in the trained aged rats. Huperzine A (0.4 mg/kg, s.c.) significantly reversed the memory deficits induced by scopolamine. CONCLUSION: Huperzine A ameliorates the impaired memory naturally occurring or induced by scopolamine in aged rats.     

酒精性肝损伤大鼠细胞色素P450 CYP2E1和细胞色素P450 CYP3A的代谢活性

目的观察酒精性肝损伤对大鼠细胞色素P450CYP3A(CYP3A)和细胞色素P450CYP2E1(CYP2E1)代谢活性的影响。方法采用ig给予白酒制备大鼠酒精性肝损伤模型,检测血清中谷丙转氨酶(GPT)和谷草转氨酶(GOT)活性,采用HE染色法光镜下观测酒精对肝脏损伤程度。大鼠ip给予CYP3A探针药物咪达唑仑10mg·kg-1或ig给予CYP2E1探针药物氯唑沙宗50mg·kg-1后,采用高效液相色谱法测定不同时间点大鼠血浆中咪达唑仑和氯唑沙宗的血药浓度,并应用3P87软件计算其药代动力学参数,以考察CYP2E1和CYP3A的代谢活性的变化。大鼠ig给予氯唑沙宗80mg·kg-1后,热板方法测定大鼠添足次数和添足反射潜伏期。结果酒精性肝损伤可致大鼠肝小叶结构不清,肝索排列紊乱,肝细胞体积增大,呈弥漫性中度水变性,肝窦受压,大部分肝细胞胞浆内见大小不等的脂肪空泡;与正常对照组相比,酒精性肝损伤组大鼠GPT和GOT活性分别增加了16.0%和20.0%(P<0.05,P<0.01)。酒精性肝损伤致大鼠CYP2E1对探针药物氯唑沙宗的代谢活性增强,AUC,t1/2和cmax分别降低了38.0%,30.5%和35.0%(P<0.05);酒精肝损伤组大鼠氯唑沙宗镇痛效果明显降低;酒精性肝损伤致大鼠CYP3A对探针药物咪达唑仑的代谢活性增强,AUC,t1/2和cmax分别降低了122.6%,54.9%和56.9%(P<0.01,P<0.05)。结论酒精性肝损伤可使大鼠CYP2E1和CYP3A代谢活性增强。     

氟他胺和2—羟基氟他胺对大鼠原代培养肝细胞毒性及CYP1A2mRNA的影响

目的:比较氟他胺及其活性代谢产物2-羟基氟他胺对原代培养大鼠肝细胞毒性及对CYP1A2 mRNA的影响.方法:分离大鼠肝细胞,原代培养4h,台酚蓝拒染法检测肝细胞活力.氟他胺和2-羟基氟他胺在培养液中浓度分别为10、20和50mg/L.肝细胞毒性检测包括台酚蓝拒染法,乳酸脱氢酶(LDH)释放量,谷丙转氨酶(AST)和谷草转氨酶(ALT)释放百分比,谷胱甘肽(GSH)含量.同时采用Northern blot方法进一步研究两药对CYP1A2 mRNA的影响.结果:药物作用8h后,氟他胺三个剂量组和2-羟基氟他胺50mg/L组出现肝细胞损伤,表现为ALT和AST释放百分比增加,GSH含量下降.氟他胺三个剂量组使CYP1A2 mRNA水平分别升高2,5和7.5倍,而2-羟基氟他胺仅在50mg/L时使CYP1A2mRNA水平升高3.5倍.结论:氟他胺对原代培养大鼠肝细胞的毒性大于其活性代谢物2-羟基氟他胺,且明显增加CYP1A2 mRNA水平.     

大黄素对大鼠肝脏CYP450酶的诱导研究

目的 探讨大黄素对大鼠肝脏细胞色素P450酶(CYP450)及其主要亚型的影响。方法 20只雄性SD大鼠, 随机分成4组, 每组5只, 分别为溶剂对照组, 170、500和1 500 mg/kg大黄素染毒组, 大黄素蒸馏水混悬后连续经口给药16 d, 结束后次日取大鼠肝脏组织制作微粒体, 分别采用CO还原差示光谱法、分光光度法及化学发光法检测大鼠肝脏微粒体总CYP450水平, 红霉素脱甲基酶(CYP3A)、氨基比啉-N-脱甲基酶, CYP1A、CYP2B和CYP2E1酶活性变化。结果 大黄素连续经口给药16 d, 能够引起大鼠肝脏微粒体总CYP450显著升高、可轻度诱导CYP3A、CYP1A、CYP2E1和CYP2B酶, 500 mg/kg剂量组最明显。结论 大黄素对大鼠肝脏中CYP3A、CYP1A、CYP2B和CYP2E1酶均有诱导作用。