Characterization of N-glucuronidation of the lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) in human liver: importance of UDP-glucuronosyltransferase 1A4.

The nicotine-derived tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), is one of the most potent and abundant procarcinogens found in tobacco and tobacco smoke and is considered to be a causative agent for several tobacco-related cancers. Glucuronidation of the major metabolite of NNK, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), has been implicated as an important mechanism for NNK detoxification. To characterize NNAL metabolism by N-glucuronidation in humans, high-pressure liquid chromatography was used to detect glucuronide conjugates of NNAL formed in human liver microsomes in vitro. In addition to peaks corresponding to the O-glucuronides of NNAL (NNAL-O-Gluc), a second series of peaks were observed in human liver microsomes that were identified by liquid chromatography-mass spectrometry to be NNAL N-glucuronides (NNAL-N-Gluc). Microsomes prepared from liver specimens from individual subjects (n = 42) exhibited substantial variability in the levels of NNAL-N-Gluc (49-fold variability) and NNAL-O-Gluc (49-fold variability) formed in vitro. This variability was likely not due to differences in tissue quality, as substantial variability (5-fold) was also observed in the ratio of NNAL-N-Gluc/NNAL-O-Gluc formation, with a mean ratio of 1.7 in the 42 specimens. Liver microsomes from smokers (n = 14) exhibited no significant difference in the levels of either NNAL-N-Gluc or NNAL-O-Gluc formation, or in the ratio of NNAL-N-Gluc/NNAL-O-Gluc formation, as compared with liver microsomes from never smokers (n = 28). Overexpressed UDP-glucuronosyltransferase (UGT) 1A4 exhibited significant levels of N-glucuronidating activity (V(max)/K(m) = 3.11 microl. min(-1). g(-1)) in vitro; no NNAL-N-glucuronide formation was detected for the 11 other overexpressed UGT enzymes tested in these studies. These results demonstrate the importance of N-glucuronidation in the metabolism of NNAL and the role of UGT1A4 in this pathway.     

Brain IL-1 beta was involved in reserpine-induced behavioral depression in rats.

AIM: To investigate the mechanism of brain interleukin-1 beta (IL-1 beta) in reserpine-induced behavioral depression in rats. METHODS: Porsult swim test was used in the measurement of depressive behavior and ELISA was used in measurement of brain IL-1 beta. RESULTS: Intraperitoneal injection of reserpine (0, 4, 6, and 8 mg/kg, ip) increased floating time in the Porsult swim test in a dose-and time-dependent manner in rats. Intracerebroventricular injection (icv) of IL-1 beta receptor antagonist (IL-1ra, 6 mg/kg) blocked the increment of floating time in Porsult swim test at 48 and 72 h after reserpine injection, but not at 1 and 24 h after injection. Brain IL-1 beta increased after reserpine treatment in posterior cortex, hippocampus, and hypothalamus. The increase of IL-1 beta concentration starts at 24 hours after injection of reserpine and reached the peak at 48 h. CONCLUSION: Reserpine induced behavioral depression partially via brain interleukin-1 beta generation.     

酸枣仁汤药效的影响因素研究

目的　对影响酸枣仁汤药效的因素进行研究。方法　采用均匀设计的方法 ,以旷野法的自发活动次数为指标 ,对影响酸枣仁汤药效的三个因素 :药物剂量、起效时间及给药天数进行研究。结果　三个因素中对自发活动次数影响大小依次为 :给药天数 >起效时间。在选定的剂量范围内 ,自发活动次数与剂量之间无线性关系 ;与给药天数、给药后起效时间有依赖关系 ,且给药天数、给药后起效时间与自发活动次数呈正相关。结论　自发活动次数最少的因素组合为 :给药 1天 ,给药后30min后进行实验 ,药物剂量为 12g/kg。为本方的药理研     

RP-HPLC法测定汉防己甲素的血药浓度

目的 :测定汉防己甲素在家兔血浆中的浓度。方法 :采用兔耳缘静脉注射给药方式 ,按不同时间间隔颈动脉取血 ,采用HypersilODS C18柱 ,以甲醇 水 ( 4 5∶5 5 )为流动相 ,检测波长 2 10nm ,以延胡索乙素为内标。结果 :标准曲线回归方程为Y =0 .5 318X 0 .0 6 88,(γ =0 .996 2 ) ,汉防己甲素在 0 .5 6 2 5～ 18μg·ml-1浓度范围内与峰面积比值呈良好的线性关系 ,平均加样回收率 88.5 % ,日内及日间RSD分别为 3.1%和 4 .7%。结论 :本方法简便、快速、可靠 ,可为汉防己甲素的其他生物样品分析提供参考     

高效液相色谱法测定香薷药材中香芹酚和百里香酚的含量

目的 :建立香薷药材中香芹酚和百里香酚的含量测定方法。方法 :用高效液相色谱法 ,95 %乙醇超声提取 ,色谱柱InertsilODS-3,流动相甲醇 水 冰醋酸 (60∶40∶2 ) ,检测波长 274nm。结果 :香芹酚在 023～215μg (r=0.9999) ,百里香酚在 039～236μg (r =0.9999)有良好的线性关系 ;平均回收率分别为香芹酚 99.9% (RSD 1.4 % ) ,百里香酚 98.6 % (RSD 1.3% ) ,重复性的RSD分别为香芹酚 1.1% ,百里香酚 1.6 %。结论 :该方法可靠、便捷 ,可以作为控制香薷药材质量的方法。     

糖网一号对糖尿病大鼠早期视网膜毛细血管病变的影响

目的观察糖尿病大鼠视网膜毛细血管超微结构的病理改变及中药复方糖网一号对毛细血管超微结构的影响.方法链尿佐菌素(STZ)致糖尿病大鼠随机分为糖尿病模型组(M)、二甲双胍组(A)、糖网一号小剂量组(B)及糖网一号大剂量组(C)(n=12),并设正常对照组(CON).每日灌药1次,6个月后测血流变指标,取视网膜行视网膜血管铺片及透射电镜观察.结果糖网一号和二甲双胍组血流变检测,两药相比,前者优于后者,糖网一号大剂量疗效优于小剂量用药.糖尿病6个月时模型组大鼠的血液有高凝、高粘现象,并出现了影周细胞、周细胞减少、微血管瘤等早期糖尿病视网膜病变的特征性改变.其余各组视网膜病变与模型组相比明显较轻,大剂量用药组接近正常.结论大鼠糖尿病早期眼底和视网膜微血管超微结构已有改变,中药糖网一号对早期糖尿病大鼠视网膜病变具有良好的防治作用.     

应用位点特异性引物鉴定白花蛇舌草

目的:建立一种简便实用的白花蛇舌草药材的DNA分子鉴定方法.方法:收集目前市场上出现的白花蛇舌草及伪品共9种,分别提取总DNA,扩增rDNA ITS-2区序列,对比所有样品的该段核苷酸序列,并设计能专一性鉴别白花蛇舌草的位点特异性引物.结果:白花蛇舌草及其混淆品在ITS-2区的序列有显著差异.用位点特异性引物对所有样品DNA进行PCR扩增,只有白花蛇舌草有明显的约392 bp扩增产物,而其它8种植物在同等条件下无阳性产物.结论:所设计的鉴别引物对白花蛇舌草有高度的特异性.     

矫形药枕治疗颈椎病临床研究

为观察矫形药枕治疗各型颈椎病的疗效,将200例颈椎病按来诊顺序随机分为两组,以针灸治疗为对照组,以针灸加药枕矫形治疗为观察组.结果显示两组资料经统计学处理,总有效率及治愈率均有明显差异(P＜0.01),具有非常显著意义.表明矫形药枕治疗颈椎病有确切疗效.     

舒筋活络洗剂治疗骨折后关节挛缩的临床研究

为客观评价舒筋活络洗剂治疗骨折后关节挛缩的作用及不良反应.将100例骨折后关节挛缩的患者随机均分为治疗组和对照组,治疗组用舒筋活络洗剂,对照组有红花油,分别于用药后3、5、7天进行评分,并将评分结果统计分析.结果显示:①治疗组显愈率为88.00%,对照组显愈率为54.00%,两组比较(P《0.01),治疗组对于症候的改善作用优于对照组;②舒筋活络洗剂无毒副作用.表明舒筋活络洗剂是治疗骨折后关节挛缩有效而且安全的药物.     

固肾止漏胶囊对大鼠子宫平滑肌收缩功能的影响

目的:观察固肾止漏胶囊含药血清对大鼠子宫平滑肌收缩功能的影响.方法:连续给药10天获取含药血清观察其对于大鼠离体子宫收缩活动的影响.结果:固肾止漏胶囊含药血清可使大鼠离体子宫收缩率明显增加,收缩频率明显增加.结论:固肾止漏胶囊有增加子宫平滑肌收缩力的作用,可能是其治疗崩漏的机理之一.