非诺贝特对高胆固醇血症兔脂肪细胞摄取及降解氧化型低密度脂蛋白的影响

目的　观察兔脂肪细胞通过CD36摄取及降解氧化型低密度脂蛋白(OxLDL)的作用和非诺贝特对高胆固醇血症兔脂肪细胞OxLDL代谢的影响。方法　10只新西兰白兔给予高胆固醇饲料饲养8周后分为: (1)高胆固醇血症组:继续饲以高胆固醇饲料4周; (2)非诺贝特治疗组:在饲以高胆固醇饲料的基础上给予(30mg·kg-1·d-1 )非诺贝特4周。另选饲以普通饲料12周兔5只作为对照组。实验结束后,取皮下脂肪组织行脂肪细胞培养,放射配基法测定脂肪细胞对OxLDL的摄取及降解,RT PCR测定脂肪细胞CD36mRNA的表达。结果　喂饲胆固醇组血清总胆固醇、低密度脂蛋白胆固醇水平明显高于对照组(均P<0. 01),非诺贝特干预4周未对血脂产生影响,但能降低体重( -19%,P<0. 05 )。RT PCR示CD36在脂肪细胞分化过程中被诱导表达。放射配基实验发现兔脂肪细胞呈浓度依赖饱和型的摄取及降解OxLDL,细胞最大结合为2 065ng/mg细胞蛋白,解离常数(Kd)为4. 2mg/L;抗CD36抗体明显抑制脂肪细胞摄取(56% )及降解(54% )OxLDL;当125I OxLDL浓度为75mg/L时,对照组,高胆固醇组,非诺贝特治疗组脂肪细胞摄取125I OxLDL分别为3. 5, 2. 1, 2. 7μg/mg细胞蛋白, 降解125I OxLDL分别为2. 2, 1. 2,1. 7μg/mg细胞蛋白, 3组间差异有统计学意义(P<0. 05)。结论　CD36介导脂     

烟酸对高脂血症兔瘦素、过氧化体增殖物激活型受体γ和CD36表达的影响

目的探讨烟酸对高脂血症兔血清瘦素及皮下脂肪组织瘦素、过氧化体增殖物激活型受体γ及CD36 mRNA表达的影响。方法12只健康雄性新西兰兔给予高胆固醇饮食饲养8周后,随机分为高脂组和烟酸组:高脂组继续饲以高胆固醇饲料6周;烟酸组在饲以高胆固醇饲料的基础上给予烟酸0.2g/(kg.d),共6周。另选择普通饮食14周兔(n=6)作为对照组。实验结束后,取腹股沟处皮下脂肪组织称重并冻存,用酶联免疫吸附法测定血清及脂肪细胞培养基瘦素水平;半定量逆转录聚合酶链反应测定脂肪组织瘦素、过氧化体增殖物激活型受体γ及CD36mRNA的表达。此外,在体外观察不同浓度的烟酸对高脂兔脂肪细胞瘦素、过氧化体增殖物激活型受体γ及CD36 mRNA的表达。结果高脂组兔血清及脂肪组织瘦素水平明显高于正常对照组,烟酸治疗6周后可降低血清及脂肪组织瘦素水平。逆转录聚合酶链反应表明烟酸组较高脂组瘦素mRNA表达降低,瘦素mRNA与过氧化体增殖物激活型受体γmRNA和CD36 mRNA的表达呈负相关。体外实验亦表明,烟酸呈剂量依赖性地降低脂肪细胞瘦素mRNA表达,并剂量依赖性地上调过氧化体增殖物激活型受体γ及CD36 mRNA的表达。结论烟酸治疗能降低高脂血症兔血清及脂肪分泌瘦素水平,上调过氧化体增殖物激活型受体γ及CD36 mRNA的表达。     

非诺贝特对高胆固醇血症兔体重及脂肪组织过氧化体增殖物激活受体表达的影响

目的 :观察非诺贝特短期干预对高胆固醇血症兔体重和皮下脂肪量的影响 ,并阐明其可能机制。方法 :10只新西兰大白兔给予高胆固醇饲料饲养 8周后 ,随机分为两组 :①高胆固醇组 :继续饲以高胆固醇饲料 4周 ;②治疗组 :在饲以高胆固醇饲料的基础上给予非诺贝特 (30mg·kg-1·d-1) ,共 4周。另选普通饮食 12周兔 (5只 )作为对照组。实验结束后 ,取皮下脂肪组织称量 ,并行前脂肪细胞培养 ,应用半定量逆转录多聚酶链式反应(RT PCR)测定脂肪组织和细胞PPARγ和PPARαmRNA的表达。结果 :高胆固醇组血清总胆固醇、低密度脂蛋白胆固醇水平明显高于对照组 (P <0 .0 1) ,非诺贝特干预 4周未对血脂产生影响 ,但能降低体重及皮下脂肪量(均P <0 .0 5 ) ,RT PCR结果显示高胆固醇组脂肪组织PPARγmRNA表达高于对照组 [(0 .5 75± 0 .14 )∶(0 .4 2 5± 0 .0 8) ,P <0 .0 5 ],非诺贝特能降低高胆固醇饲养兔脂肪组织PPARγmRNA表达 [(0 .4 78± 0 .11)∶(0 .5 75±0 .14 ) ,P >0 .0 5 ],并呈剂量依赖性的降低前脂肪细胞PPARγmRNA表达。 3组兔脂肪组织PPARαmRNA表达差异无统计学意义。结论 :非诺贝特独立于降脂作用外 ,能降低高胆固醇血症兔体重和皮下脂肪量 ,其机制之一可能与下调脂肪细胞PPARγmRNA表达有关。这一作用可     

非诺贝特抑制脂肪细胞组织因子表达

为探讨动脉粥样硬化兔脂肪细胞组织因子表达及非诺贝特对其的影响 ,将 15只兔随机分为正常组、动脉粥样硬化组和非诺贝特组 ,非诺贝特组在高胆固醇饮食第 9周起加用非诺贝特 (每天 30mg/kg)干预 4周 ,采用逆转录聚合酶链反应测定脂肪细胞组织因子的表达。结果发现 ,高胆固醇饮食可显著升高血清总胆固醇 (P <0 .0 5 ) ,甘油三酯无明显升高 ;加用非诺贝特治疗 4周 ,总胆固醇和甘油三酯均无明显改变。动脉粥样硬化组脂肪细胞组织因子表达明显高于正常组 (1.0 81± 0 .0 11比 0 .939± 0 .0 18,P <0 .0 1) ,非诺贝特治疗 4周后组织因子表达较动脉粥样硬化组显著降低 (0 .893± 0 .0 2 2比 1.0 81± 0 .0 11,P <0 .0 1)。结果提示 ,动脉粥样硬化组兔脂肪细胞表达组织因子明显增加 ,非诺贝特能抑制其表达 ,提示非诺贝特可能具有抗血栓作用     

过氧化体增殖物激活型受体γ对巨噬细胞脂质蓄积及CD36表达的影响

目的观察过氧化体增殖物激活型受体γ激动剂和拮抗剂对THP-1巨噬细胞胆固醇蓄积及CD36表达的影响。方法实验分对照组、氧化型低密度脂蛋白组、Ciglitazone处理组和GW9662处理组,后两组用50 mg/L氧化型低密度脂蛋白分别与过氧化体增殖物激活型受体γ激动剂Ciglitazone(10μmol/L)及拮抗剂GW9662(10μmol/L)共同孵育24 h,高效液相色谱分析法检测细胞总胆固醇蓄积情况,RT-PCR和Western blot分别检测THP-1巨噬细胞CD36 mRNA和蛋白的表达。结果与对照组(76.28±10.36 mg/g)相比,氧化型低密度脂蛋白(121.63±13.32 mg/g)能使细胞总胆固醇含量显著增加,而Ciglitazone能使氧化型低密度脂蛋白处理的细胞总胆固醇含量进一步增加(136.23±14.78 mg/g),GW9662能使氧化型低密度脂蛋白处理的细胞总胆固醇含量减少(98.52±11.45 mg/g)。过氧化体增殖物激活型受体γ拮抗剂GW9662使巨噬细胞CD36 mRNA和蛋白的表达下调及胆固醇蓄积减少,过氧化体增殖物激活型受体γ激动剂Ciglitazone使巨噬细胞CD36 mRNA和蛋白的表达上调及胆固醇蓄积增多。结论过氧化体增殖物激活型受体γ拮抗剂使THP-1巨噬细胞胆固醇蓄积减少及氧化型低密度脂蛋白诱导的CD36表达下调。     

阿托伐他汀对THP-1巨噬细胞脂质蓄积及CD36表达的影响

目的观察阿托伐他汀对氧化型低密度脂蛋白诱导的THP-1巨噬细胞脂质蓄积及CD36表达的影响。方法用50mg/L氧化型低密度脂蛋白与不同浓度的阿托伐他汀(0、0.312、1.25和5μmol/L)共同孵育THP-1巨噬细胞24h,以空白组作对照,用液体闪烁计数法检测细胞[3H]胆固醇流入情况,油红O染色观察细胞内脂质蓄积情况,高效液相色谱分析法检测细胞内总胆固醇水平,逆转录聚合酶链反应与免疫印迹分析法分别检测THP-1巨噬细胞CD36mRNA和蛋白的表达。结果阿托伐他汀使THP-1巨噬细胞胆固醇流入减少,对照组胆固醇流入为35.90%±2.36%,0、0.312、1.25和5μmol/L阿托伐他汀组胆固醇流入分别为47.10%±3.18%、41.20%±2.88%、35.10%±2.35%和28.30%±1.98%;阿托伐他汀能抑制THP-1巨噬细胞对氧化型低密度脂蛋白的摄取,油红O染色可见氧化型低密度脂蛋白 阿托伐他汀组细胞内脂滴较氧化型低密度脂蛋白组明显减少,且脂滴颗粒体积变小;高效液相色谱分析发现,对照组细胞总胆固醇含量为78.24±11.35mg/g,0、0.312、1.25和5μmol/L阿托伐他汀组细胞总胆固醇含量分别为123.13±15.92mg/g、115.36±13.18mg/g、107.52±12.05mg/g和98.03±10.24mg/g。阿托伐他汀使氧化型低密度脂蛋白诱导的THP-1巨噬细胞CD36mRNA和蛋白的表达下调。结论阿托伐他汀引起氧化型低密度脂蛋白诱导的THP-1巨噬细胞CD36表达下调,并使脂质蓄积减少。     

非诺贝特对高胆固醇喂养兔主动脉斑块面积和肿瘤坏死因子α的影响

目的利用高脂饮食诱发动脉粥样硬化模型,观察非诺贝特的抗动脉粥样硬化作用,并探讨其机制。方法10只新西兰大白兔给予高胆固醇饮食饲养8周后,随机分为两组:高胆固醇组继续饲以高胆固醇饲料4周;非诺贝特组在饲以高胆固醇饲料的基础上给予非诺贝特[30 mg/(kg.d)],共4周。另选择普通饮食12周兔(n=5)作为对照组。测定饲养前后血清肿瘤坏死因子α水平和饲养后的主动脉斑块面积。半定量逆转录聚合酶链反应测定脂肪组织肿瘤坏死因子αmRNA的表达。结果非诺贝特组和高胆固醇组血清总胆固醇、低密度脂蛋白胆固醇水平均明显高于对照组(P<0.001),但两组间差异无显著性。非诺贝特组与高胆固醇组相比主动脉斑块面积(52.81%±6.92%比76.30%±8.61%,P<0.01)、血管内膜厚度(28.45±5.68μm比76.18±11.25μm,P<0.05)、血清肿瘤坏死因子α水平(2.11±0.26 ng/L比3.86±0.33 ng/L,P<0.05)以及脂肪组织肿瘤坏死因子αmRNA表达量(0.31±0.05比0.56±0.07,P<0.05)均显著降低。结论非诺贝特具有一定的抗动脉粥样硬化作用,其降低高胆固醇喂养兔血清肿瘤坏死因子α水平可能是其作用机制之一。     

苯扎贝特对脐静脉内皮细胞内皮型一氧化氮合酶表达的影响及机制

目的 观察苯扎贝特对氧化型低密度脂蛋白所诱导的人脐静脉内皮细胞内皮型一氧化氮合酶表达的影响及是否与血凝素样氧化型低密度脂蛋白受体1表达相关.方法 体外培养人脐静脉内皮细胞,逆转录聚合酶链反应检测内皮型一氧化氮合酶及血凝素样氧化型低密度脂蛋白受体1mRNA表达,Western Blot检测内皮型一氧化氮合酶及血凝素样氧化型低密度脂蛋白受体1蛋白含量表达.结果 与氧化型低密度脂蛋白组比较,苯扎贝特组和多聚肌苷酸(血凝素样氧化型低密度脂蛋白受体1阻断剂)组内皮型一氧化氮合酶mRNA和蛋白表达均增加,血凝素样氧化型低密度脂蛋白受体1mRNA和蛋白表达均减少(P＜0.05);与苯扎贝特组比较,苯扎贝特组+多聚肌苷酸组内皮型一氧化氮合酶mRNA和蛋白表达均明显增加,血凝素样氧化型低密度脂蛋白受体1mRNA和蛋白表达均明显减少(P＜0.01).结论 血凝素样氧化型低密度脂蛋白受体1可能介导苯扎贝特上调内皮细胞内皮型一氧化氮合酶基因和蛋白的表达.     

吉非罗齐对高脂血症兔心肌缺血再灌注损伤的影响及机制

目的探讨吉非罗齐对高脂血症兔心肌缺血再灌注损伤的影响。方法24只新西兰大白兔随机分成缺血再灌注组、吉非罗齐 缺血再灌注组(简称吉非罗齐组)和假手术组,所有动物给以高脂饮食9周以建立高脂血症兔模型,吉非罗齐组在喂养8周后同时给予吉非罗齐200mg(kg·d)口服1周。冠状动脉左前降支结扎法复制心肌缺血再灌注损伤模型。9周后观察各组血脂水平的变化及心肌细胞超微结构改变,并测定心肌梗死面积。逆转录聚合酶链反应测定心肌过氧化体增殖物激活型受体α和脂肪酸转位酶CD36 mRNA的表达。结果喂饲高脂饮食后,兔血清总胆固醇、低密度脂蛋白胆固醇水平明显升高(P<0.01),吉非罗齐干预1周未对血脂水平产生影响。吉非罗齐组心肌梗死面积较缺血再灌注组明显减少(P<0.05);且心肌细胞超微结构损伤明显低于缺血再灌注组。缺血再灌注组心肌过氧化体增殖物激活型受体α和CD36 mRNA的表达低于假手术组(P<0.05),而吉非罗齐组与假手术组过氧化体增殖物激活型受体α和CD36 mRNA的表达无明显差异(P>0.05)。结论吉非罗齐短期干预可减少高脂血症兔缺血再灌注后心肌梗死面积,并上调心肌过氧化体增殖物激活型受体α和CD36 mRNA的表达。     

非诺贝特对兔脂联素基因和蛋白表达的影响

目的观察非诺贝特对培养的兔脂肪细胞分泌脂联素的影响,并探讨其可能机制。方法取兔腹股沟皮下脂肪组织行脂肪细胞培养,将含不同终浓度[0(对照组)、1、10、50、100μmol/L]非诺贝特的培养液与定量培养的兔脂肪细胞在培养箱中孵育24h,另将终浓度为50μmol/L非诺贝特的培养液与定量培养的兔脂肪细胞分别作用0、4、8、12、24h。用酶联免疫吸附法(ELISA)检测脂肪细胞培养液中脂联素蛋白水平,用半定量逆转录多聚酶链式反应(RT-PCR)测定脂肪细胞脂联素mRNA的表达。结果①1μmol/L及10μmol/L非诺贝特作用24h对脂肪细胞脂联素mRNA及蛋白表达均无影响。而50μmol/L非诺贝特对脂肪细胞脂联素mRNA及蛋白表达呈促进作用,与对照组相比,脂联素mRNA的表达上升32.8%,蛋白的分泌上升24.3%。100μmol/L非诺贝特作用24h使脂肪细胞脂联素mRNA的表达上升58.5%,蛋白的分泌上升33.9%。②50μmol/L非诺贝特作用4h及8h对脂肪细胞脂联素基因及蛋白表达无影响,作用12h促进脂联素mRNA的表达及蛋白的分泌,与对照组相比mRNA的表达上升27.1%,蛋白含量上升23.1%。50μmol/L非诺贝特作用24h,脂肪细胞脂联素mRNA的表达升高35.7%,蛋白的分泌升高32.1%。结论非诺贝特对脂肪细胞脂联素基因表达及蛋白的分泌有促进作用,与剂量和作用时间呈正相关。     

妊娠时间与肺结核复发的相关性研究及诊治对策

目的 分析肺结核史患者妊娠时间和肺结核复发间相关性.方法 选取我院收治的有肺结核史的妊娠妇女576例作为研究对象,对其妊娠前肺结核治疗、治愈后妊娠时间、妊娠后复发肺结核等进行分析,总结有肺结核史育龄女性的妊娠时间和肺结核复发之间的关系.结果 肺结核治愈后不同时间段妊娠者的结核复发率比较,差异具有显著性（P＜0.05）,停药后间隔时间越久妊娠,肺结核复发的几率越小.结论 加强孕期痰菌检查,及早发现复发肺结核,提高母婴安全.     

我国骨关节结核诊治的回顾与展望

骨关节结核是危害人们健康的严重感染性疾病,近95％由他处结核病继发而来.罹患骨关节结核疾病后几乎均将致残,严重影响人们的健康、工作和生活.建国以来在党和国家的关心和支持下,骨关节结核的诊治水平取得了长足进步.时至今日,由于多种原因,学科发展和被重视程度受到一定的制约,同整个医疗行业的发展不相适应.回顾过去,展望未来,我们需要重新审视骨关节结核的诊治方法,努力推进骨关节结核诊疗技术的科学发展.     

Effect of phosphorylation of MAPK and Stat3 and expression of c-fos and c-jun proteins on hepatocarcinogenesis and their clinical significance

AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44~(MAPK), p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44~(MAPK), p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44~(MAPK) and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between P42/44~(MAPK) and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Raf/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44~(MAPK), c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis.     

Overweight and Obesity and Progression of ADPKD

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Replication and Inhibitors of Enteroviruses and Parechoviruses

The Enterovirus (EV) and Parechovirus genera of the picornavirus family include many important human pathogens, including poliovirus, rhinovirus, EV-A71, EV-D68, and human parechoviruses (HPeV). They cause a wide variety of diseases, ranging from a simple common cold to life-threatening diseases such as encephalitis and myocarditis. At the moment, no antiviral therapy is available against these viruses and it is not feasible to develop vaccines against all EVs and HPeVs due to the great number of serotypes. Therefore, a lot of effort is being invested in the development of antiviral drugs. Both viral proteins and host proteins essential for virus replication can be used as targets for virus inhibitors. As such, a good understanding of the complex process of virus replication is pivotal in the design of antiviral strategies goes hand in hand with a good understanding of the complex process of virus replication. In this review, we will give an overview of the current state of knowledge of EV and HPeV replication and how this can be inhibited by small-molecule inhibitors.     

Effect of phosphorylation of MAPK and Stat3 and expression of c-fas and c-jun proteins on hepatocarcinogenesis and their clinical significance

AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44MAPK, p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44MAPK, p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44MAPK and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between p42/44MAPK and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Rat/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44MAPK, c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis.     

心电图、心电向量图与冠状动脉造影结果对比分析

目的:通过分析心电图(Electrocardiogram,ECG)和心电向量图(Vectorcardiogram,VCG)的改变与冠脉造影（CAG）结果进行对比,探讨ECG、VCG在冠状动脉病变中的诊断价值。方法: 选择2008年1月~2009年12月临床拟诊断为冠心病患者108例,行常规ECG、VCG检查,并于1周内进行CAG,对检查结果依据各自的诊断标准进行判定,以CAG为标准诊断法,利用四格表法,计算相关评价真实性的指标并进行比较。结果: ①VCG检测的灵敏度、特异度、准确度显著高于ECG(P<0.05,P<0．01)。②ECG、VCG阳性率与冠脉病变支数组间比较:在单支病变、双支病变中,VCG阳性率明显高于ECG(P<0.05),左主干或三支病变无统计学意义;组内比较:ECG组左主干或三支病变组较单支病变、双支病变阳性率高(P<0.05,P<0.01);VCG组左主干或三支病变组较单支病变阳性率高(P<0.05);与双支病变阳性率比较无统计学意义;③ECG、VCG阳性率与冠脉病变程度组间比较:冠脉病变狭窄50%～69%的VCG阳性率明显高于ECG (P<0.05),其他两组阳性率比较无统计学意义;组内比较:ECG组冠脉病变狭窄≥90%较50%～69%、70%～89%的阳性率高(P<0.05,P<0.01); VCG组狭窄≥90%较50%～69%阳性率高（P<0.01),其他无统计学意义。结论: VCG对冠心病检测价值显著高于ECG。     

Detection and characterization of the product of hydroethidine and intracellular superoxide by HPLC and limitations of fluorescence

Here we report the structural characterization of the product formed from the reaction between hydroethidine (HE) and superoxide (O(2)(.-)). By using mass spectral and NMR techniques, the chemical structure of this product was determined as 2-hydroxyethidium (2-OH-E(+)). By using an authentic standard, we developed an HPLC approach to detect and quantitate the reaction product of HE and O(2)(.-) formed in bovine aortic endothelial cells after treatment with menadione or antimycin A to induce intracellular reactive oxygen species. Concomitantly, we used a spin trap, 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide (BMPO), to detect and identify the structure of reactive oxygen species formed. BMPO trapped the O(2)(.-) that formed extracellularly and was detected as the BMPO-OH adduct during use of the EPR technique. BMPO, being cell-permeable, inhibited the intracellular formation of 2-OH-E(+). However, the intracellular BMPO spin adduct was not detected. The definitive characterization of the reaction product of O(2)(.-) with HE described here forms the basis of an unambiguous assay for intracellular detection and quantitation of O(2)(.-). Analysis of the fluorescence characteristics of ethidium (E(+)) and 2-OH-E(+) strongly suggests that the currently available fluorescence methodology is not suitable for quantitating intracellular O(2)(.-). We conclude that the HPLC/fluorescence assay using HE as a probe is more suitable [corrected] for detecting intracellular O(2)(.-).     

Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice

Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology.     

大鼠骨髓间充质干细胞的分离培养和外源基因的导入

目的探讨绿色荧光蛋白基因转染骨髓间质干细胞的可行性。方法采用F icoll-PaqueTMP lus淋巴细胞分离液,根据细胞密度梯度原理,分离大鼠骨髓间充质干细胞(rM SC s)并进行体外原代培养和传代扩增,倒置相差显微镜观察细胞生长情况,免疫细胞化学法对其初步鉴定。流式细胞仪分析转染效率。结果原代和传代培养的细胞呈现梭形外观,具有较强的生长增殖能力;细胞均一表达CD44、CD54、CD106、CD29抗原。电穿孔法转染rM SC s转染率为32.8%±3%。结论采用比重为1.077 g/L的F icoll-PaqueTMP lus能分离获得大鼠骨髓间充质干细胞,经原代培养和传代培养能够迅速扩增。电穿孔法具有较高的介导外源基因表达于rM SC s的效率。