莫西沙星灌胃给药在肺炎大鼠血液及肺组织中的药代动力学特点分析

目的研究莫西沙星灌胃给药在肺炎大鼠血液及肺组织中的药代动力学特点。方法首先采用灌胃给药的方式给肺炎链球菌肺炎大鼠模型灌莫西沙星,其次利用微透析技术对肺炎大鼠进行血液和肺部附近组织同时采样的操作,然后使用液相色谱法对莫西沙星的分散药量进行测量,最后计算并分析药代动力学指标。实验后,观察肺炎大鼠血液和肺组织的T_(max)、C_(max)、t_(1/2)A、UC0-∞AUC肺/AUC血液药代动力学参数。结果血液和肺组织内的游离药物的T_(max)、C_(max)数值都比较高,在二者同时减小之后,药物在肺部的穿透率比再血浆中大的多。与此同时,在血液内消除半衰期(t_(1/2))比肺组织内的小,差异显著,P <0.05。结论莫西沙星灌胃给药一定的剂量下,肺炎大鼠体内的药物有助于更好的消除肺炎链球菌,从而得到好的治疗。     

银杏叶片长期给药后对大鼠灌服氯沙坦的药代动力学影响

目的:研究银杏叶提取物(GBE)制剂银杏叶片长期给药后对大鼠灌服氯沙坦(Los)的药代动力学影响.方法:SD大鼠随机分为Los单用组,GBE+ Los联合用药组.试验第1天起,联合用药组大鼠灌胃给予GBE 100 mg/kg,共14 d.单用组大鼠灌胃给予等量纯净水.第15天,单用药组大鼠灌胃给予Los 10 mg/kg,GBE+Los联合给药组大鼠同时灌胃给予GBE 100 mg/kg和Los 10 mg/kg.于Los给药后0.5、1、2、3、4、6、8、10、12、24 h从大鼠眼眦静脉丛取血.HPLC法测定血浆中Los及其活性代谢产物EXP3174的浓度,计算其主要药代动力学参数,并进行统计学分析.结果:合用GBE后,Los的各药代动力学参数差异无统计学意义.EXP3174的tmax显著缩短(P＜0.05),Cmax、AUC0-8和AUC0-∞显著增加(P＜0.01),CL显著降低(P＜0.05),t1/2、MRT变化无统计学差异.结论:GBE能够影响EXP3174的体内代谢,但对Los的药代动力学过程影响没有统计学意义.     

七叶皂苷对洛伐他汀在高脂血症大鼠模型体内药代动力学的影响

目的在高脂血症大鼠模型中研究七叶皂苷对洛伐他汀药代动力学的影响。方法采用高脂饲料喂饲大鼠,构建高脂血症大鼠模型,通过血清生化分析确定造模成功。选择12只造模成功的大鼠,随机分成2组,即单独给药组和联合给药组,每组6只大鼠。单独给药组和联合给药组大鼠分别经尾静脉注射给予0.9%生理盐水和注射用七叶皂苷钠(0.5 mg/kg,qd),连续14 d。第14天,给药后,两组大鼠灌胃给予洛伐他汀(20 mg/kg,0.5%CMC-Na溶液),并于洛伐他汀给药前和给药后不同时间点采集血样,采用HPLC-MS/MS方法测定洛伐他汀及其活性代谢物洛伐他汀酸的血药浓度,计算药动学参数。结果长期给予七叶皂苷钠导致洛伐他汀酸的血浆暴露水平显著升高,Cmax、AUC0-t、AUC0-∞分别是单独给药组的2.43(90%CI:1.55,3.31)、2.66(90%CI:1.67,3.66)和2.99倍(90%CI:1.44,4.55),两组比较差异有统计学意义(P<0.05)。与单独给药组相比,联合给药组洛伐他汀的血浆暴露也略有增加,但两组Cmax和AUC比较差异无统计学意义(P>0.05)。结论七叶皂苷可抑制高脂血症模型大鼠的洛伐他汀代谢,增加其体内暴露水平。     

黄豆苷元对卡马西平及其代谢产物在大鼠体内药动学的影响

目的:研究黄豆苷元对卡马西平及其代谢产物10,11-环氧卡马西平(CBZ-E)在大鼠体内药动学的影响。方法:16只大鼠随机分为实验组和对照组,实验组大鼠连续10 d灌胃给予黄豆苷元100 mg.kg-1,对照组大鼠则灌胃给予等体积的生理盐水,两组大鼠第11天分别灌胃给予卡马西平10 mg.kg-1,于给药后不同时间点采血,采用HPLC法测定血浆中卡马西平及其代谢产物CBZ-E的浓度,计算药动学参数。结果:与对照组相比,实验组大鼠血浆中卡马西平的AUC0-24h、AUC0-∞、Cmax和t1/2显著增加(P<0.05),代谢产物CBZ-E的AUC0-24h、AUC0-∞和Cmax显著降低(P<0.05)。结论:黄豆苷元连续给药后改变了卡马西平在大鼠体内的药动学特征,可能与抑制CYP3A4的活性有关。     

葛根素注射液对多索茶碱在大鼠体内药动学的影响

目的研究葛根素对多索茶碱在大鼠体内药动学的影响。方法采用高效液相色谱（HPLC）法测定12只大鼠单独给药和联合葛根素给药后多索茶碱及其代谢产物茶碱的血浆浓度,采用DAS药动学软件对多索茶碱血浆浓度 时间数据进行非房室模型分析,求多索茶碱在大鼠体内的主要药动学参数,并进行统计分析。结果两组大鼠多索茶碱t1/2差异有统计学意义（P＜0.05）,合并用药组较单独用药组增加了6.65%;CL/F差异有统计学意义（P＜0.05）,合并用药组较单独用药组减少38.00%。单独给药组和合并给药组茶碱AUC（0 8）、Cmax、tmax差异无统计学意义（P＞0.05）,t1/2差异有统计学意义（P＜0.05）,合并用药组较单独用药组增加了35.29%;CL/F差异有统计学意义（P＜0.05）,合并用药组较单独用药组减少了35.29%。结论葛根素能抑制多索茶碱在大鼠体内代谢,且能延长多索茶碱代谢产物茶碱在体内的消除,两药同时使用应注意监测血茶碱浓度。     

盐酸莫西沙星片在健康志愿者体内两种条件下的药动学研究

目的 研究盐酸莫西沙星片在健康志愿者体内两种条件下的药动学.方法 采用随机交叉自身对照试验设计,24名健康男性志愿者随机交叉单剂量空腹(或餐后)口服400 mg盐酸莫西沙星片.采用HPLC-UV法测定受试者血浆中莫西沙星的浓度,计算药动学参数,评价制剂在两种条件下的药动学行为.结果 空腹条件下,盐酸莫西沙星片的主要药动学参数为:Tmax =1.55 ±0.96 h,Cmax=3.45±0.88 μg·mL-1,AUC0-t=58.77±13.02 μg·mL-1·h,AUC0-∞=60.50±13.71 μg·mL-1·h;餐后条件下,盐酸莫西沙星片的主要药动学参数为:Tmax =2.66±1.48 h,Cmax=3.16±0.70 μg·mL-1,AUC0-t=57.01±9.95μg· mL-1·h,AUC0-∞=59.00± 10.60 μg·mL-1· h.结论 餐后与空腹条件相比,除了Tmax有所延迟外,其余药动学参数均无太大差别,表明食物可能会减缓盐酸莫西沙星的吸收.     

HPLC-荧光法测定莫西沙星在犬体内的血药浓度及其药动学研究

目的:建立测定犬血浆中莫西沙星浓度的方法,并研究其药动学特性。方法:取Beagle犬6只,单剂量灌服莫西沙星120mg,采用高效液相色谱-荧光法测定给药后72 h内血浆中莫西沙星的浓度,采用DAS软件计算药动学参数。色谱柱为HypersilBDS C18,流动相为乙腈-1.0 mol.L-1醋酸溶液(25∶75,pH=2.0),流速为1.0 mL.min-1,激发波长为273 nm,发射波长为488 nm。结果:莫西沙星检测浓度的线性范围为0.1～20.0μg.mL-(1r=0.999 2),平均相对回收率为89.5%～96.7%,日内和日间RSD均<6%。莫西沙星在犬体内的药动学特性符合二室模型,主要药动学参数cmax:(10.25±4.21)μg.mL-1,tmax:(3.0±1.0)h,t1/2β:(9.76±2.48)h,AUC0～24 h:(142.10±49.80)mg.h.L-1。结论:本方法准确、灵敏、快速,适用于莫西沙星的血药浓度测定和药动学研究。     

盐酸莫西沙星片剂的血药浓度及药动学分析

目的 分析盐酸莫西沙星在人体内的血药浓度及药动学.方法 10名志愿受试者单剂量口服莫西沙星400mg后,采用固相萃取-高效液相色谱方法测定盐酸莫西沙星的血药浓度及药动学参数,用DAS2.0软件自动拟合处理,计算药动学参数.结果 莫西沙星的药动参数:t1/2α=(5.26±0.20)h;t1/2 β=(7.80±0.50)h;AUC(0～t)=(111.8±10.3)μg/ (mL·h);tmax=(3.13±0.32)h;Cmax=(13.5±0.42) μg/ mL;莫两沙星在体内的药-时曲线符合二室开放模型,在体内消除半衰期为12h,生物利用度约为95.4％.结论 该方法操作简单、准确可靠,可用于莫西沙星的临床药动学研究及临床特殊人群的血药浓度测定.     

克拉霉素对替硝唑大鼠体内药动学的影响

目的探讨克拉霉素对替硝唑大鼠体内药动学过程的影响。方法大鼠随机分为两组,每组5只,其中一组大鼠灌胃给药替硝唑后测定血浆中药物的质量浓度,另一组灌胃给药克拉霉素,连续5 d,于第6天联合给药替硝唑与克拉霉素,而后测定血浆中替硝唑药物质量浓度,计算药动学参数。用DAS软件程序进行数据处理并采用SPSS软件进行统计学分析。结果单独给药替硝唑组的主要药动学参数为:ρmax为(27.08±2.98)mg.L-1,t1/2为(2.16±0.76)h,AUC0-24 h为(138.04±5.84)mg.h.L-1。联合给药组的替硝唑主要药动学参数为:ρmax为(32.73±8.37)mg.L-1,t1/2为(2.76±1.69)h,AUC0-24 h为(160.45±7.83)mg.h.L-1。其中,两组间AUC及Cl/F存在显著性差异(P<0.05)。结论克拉霉素对替硝唑大鼠体内药动学过程影响较小。     

甘草提取物对大鼠体内环孢素药代动力学的影响

目的:研究甘草连续给药7 d对环孢素在大鼠体内的药代动力学影响。方法:12只大鼠随机分为生理盐水对照组和甘草实验组,甘草实验组予甘草提取物(0.5 g/kg,1次/d)连续给药7 d,第8天晨两组均予环孢素灌胃给药后按时间点连续采样,采用荧光偏振免疫分析法测定环孢素的血药浓度,计算并比较主要药动学参数。结果:对照组和实验组的环孢素主要药动学参数Cmax、tmax、t1/2、AUC0-48 h、AUC0-∞、平均滞留时间(MRT)、药物清除率(CL/F)、表观分布面积(V/F)差异均无统计学意义(P>0.05)。结论:甘草连续给药7 d后不影响环孢素在大鼠体内的药代动力学。     

Interaction of estrone and estradiol with DNA and protein of liver and kidney in rat and hamster in vivo and in vitro

[6,7-³H] Estrone (E) and [6,7-³H]estradiol-17 (E₂) have been synthesized by reduction of 6-dehydroestrone and 6-dehydroestradiol with tritium gas. Tritiated E and E₂ were administered by oral gavage to female rats and to male and female hamsters on a dose level of about 300 g/kg (54 mCi/kg). After 8 h, the liver was excised from the rats; liver and kidneys were taken from the hamsters. DNA was purified either directly from an organ homogenate or via chromatin. The radioactivity in the DNA was expressed in the units of the Covalent Binding Index, CBI = (mol chemical bound per mol DNA-P)/(mmol chemical administered per kg b.w.). Rat liver DNA isolated via chromatin exhibited the very low values of 0.08 and 0.09 for E and E₂, respectively. The respective figures in hamster liver were 0.08 and 0.11 in females and 0.21 and 0.18 in the males. DNA isolated from the kidney revealed a detectable radioactivity only in the female, with values of 0.03 and 0.05 for E and E₂, respectively. The values for male hamster kidney were < 0.01 for both hormones. The minute radioactivity detectable in the DNA samples does not represent covalent binding to DNA, however, as indicated by two sets of control experiments. (A) Analysis by HPLC of the nucleosides prepared by enzyme digest of liver DNA isolated directly or via chromatin did not reveal any consistent peak which could have been attributed to a nucleoside-steroid adduct. (B) All DNA radioactivity could be due to protein contaminations, because the specific activity of chromatin protein was determined to be more than 3,000 times higher than of DNA. The high affinity of the hormone to protein was also demonstrated by in vitro incubations, where it could be shown that the specific activity of DNA and protein was essentially proportional to the concentration of radiolabelled hormone in the organ homogenate, regardless of whether the animal was treated or whether the hormone was added in vitro to the homogenate.Carcinogens acting by covalent DNA binding can be classified according to potency on the basis of the Covalent Binding Index. Values of 10³–10⁴ have been found for potent, 10² for moderate, and 1–10 for weak carcinogens. Since estrone is moderately carcinogenic for the kidney of the male hamster, a CBI of about 100 would be expected. The actually measured limit of detection of 0.01 places covalent DNA binding among the highly unlikely mechanisms of action. Similar considerations can be made for the liver where any true covalent DNA binding must be below a level of 0.01. It is concluded that an observable tumor induction by estrone or estradiol is unlikely to be due to DNA binding.Paper presented at the Satellite Symposium of the European Society of Toxicology, Rome, March 29, 1983     

Consistency in catecholamine and cortisol excretion in males and females

Data from a series of experiments performed on 24 female and 24 male subjects were used to evaluate the consistency in urinary catecholamine and cortisol excretion. Data were available from 8 laboratory situations of varying activity level and content, spaced at intervals of maximum 3 months. Correlational analyses showed that for cortisol, interindividual consistency was higher for measures obtained on the same day than for measures obtained on different days. Interindividual consistency was generally high in catecholamine and cortisol excretion during non-stressful situations in both sexes. During experimental stress, however, consistency was as high as during nonstress for males, while it was lower for females. Analysis of variance components confirmed these results and showed that in males variation due to interindividual differences was high during both baseline and experimental-stress situations, while in females it was high during baseline situations only. During experimental stress, variation for females was due primarily to interaction. It is suggested that the males showed a more generalized stress response over situations than the females.     

Nicotine metabolism and urinary elimination in mouse: in vitro and in vivo

This study aimed at elucidating the in vivo metabolism of nicotine both with and without inhibitors of nicotine metabolism. Second, the role of mouse CYP2A5 in nicotine oxidation in vitro was studied as such information is needed to assess whether the mouse is a suitable model for studying chemical inhibitors of the human CYP2A6. The oxidation of nicotine to cotinine was measured and the ability of various inhibitors to modify this reaction was determined. Nicotine and various inhibitors were co-administered to CD2F1 mice, and nicotine and urinary levels of nicotine and four metabolites were determined. In mouse liver microsomes anti-CYP2A5 antibody and known chemical inhibitors of the CYP2A5 enzyme blocked cotinine formation by 85–100%, depending on the pre-treatment of the mice. The amount of trans-3-hydroxycotine was five times higher than cotinine N-oxide, and ten times higher than nicotine N-1-oxide and cotinine. Methoxsalen, an irreversible inhibitor of CYP2A5, significantly reduced the metabolic elimination of nicotine in vivo, but the reversible inhibitors had no effect. It is concluded that the metabolism of nicotine in mouse is very similar to that in man and, therefore, that the mouse is a suitable model for testing novel chemical inhibitors of human CYP2A6.     

Metabolic interaction between imipramine and carbamazepine in vivo and in vitro in rats

Summary The pharmacokinetic consequences of the combination of carbamazepine with imipramine in male Wistar rats have been investigated. It was found that a 2-week treatment with the combination resulted in the increase of the concentrations of the parent compounds and a simultaneous decrease in their metabolites in blood plasma i.e. carbamazepine inhibited imipramine demethylation in the side chain while imipramine inhibited carbamazepine 10,11-epoxidation. The velocity of imipramine 2-hydroxylation and 10,11-epoxy-carbamazepine hydration did not seem to be changed by the combination. On the basis of studies in vitro it is concluded that the observed metabolic interaction between carbamazepine and imipramine is due to the competition of the drugs for the active centre of cytochrome P 450 and to a certain qualitative alteration of the enzyme by imipramine as can be deducted from the decrease of carbamazepine binding to the cytochrome. Send offprint requests to K. J. Netter     

Buprenorphine and naloxone alone and in combination in opioid-dependent humans

Subjective, physiological and behavioral effects of subcutaneously administered hydromorphone (6 mg), naloxone (0.2 mg), buprenorphine (0.2 and 0.3 mg), and two buprenorphine-naloxone combinations (buprenorphine 0.2 mg plus naloxone 0.2 mg and buprenorphine 0.3 mg plus naloxone 0.2 mg) were assessed under double-blind conditions in six opioid-dependent volunteers. Physiologic measures and subject- and observer-rated behavioral responses were measured before dosing and for 120 min after drug administration. Hydromorphone decreased pupil diameter and respiration, increased blood pressure and increased scores on subjective measures indicating opioid-like effects. Buprenorphine given alone had no significant effect on any variable measured. Naloxone given alone produced opioid abstinence-like effects which were measurable on subject- and observer-rated behavioral measures and physiological measures. Buprenorphine in combination with naloxone somewhat attenuated the naloxone-precipitated withdrawal response. Overall, the naloxone-buprenorphine combinations produced effects which were qualitatively similar to the effects of naloxone alone, suggesting a low potential for abuse of the combination product by opioid-dependent individuals.Supported by a grant from Reckitt and Colman Pharmaceutical Division and USPHS Grants DA-00050 and DA-04089 from the National Institute on Drug Abuse     

Strain-dependency in motor activity and in concentration and turnover of catecholamines in synchronized rats

Circadian rhythm in motor activity was studied with an Animex motimeter in six strains of rats (ACI, BH, BS, DA, LEW, TNO) synchronized by a 12 hr light: 12 hr dark cycle. ANOVA revealed significant interstrain differences in motor activity as well as in the concentration and turnover of central noradrenaline and dopamine. Strain-dependent differences were also found with regard to tyrosine hydroxylase inhibition on motor activity. However, no significant interstrain correlations were found between endogenous concentration and/or turnover rates of the catecholamines and motor activity in normal and drug-treated rats.     

氯胺酮复合丙泊酚及氯胺酮复合咪达唑仑在小儿麻醉中的麻醉效果对比

目的研究氯胺酮分别复合丙泊酚和咪迟唑仑在小儿麻醉术中及术后的麻醉效果。方法 40例2⁸岁拟在全身麻醉下行择期下腹部手术患儿,不拘性别。随机数字表法分为氯胺酮复合丙泊酚组(A组),氯胺酮复合咪达唑仑组(B组),每组备20例(n=20),比较两组镇痛、镇静效果及躁动、恶心呕吐、呼吸抑制等并发症的发生率。结果两组镇痛及镇静效果均满意,但B组躁动、恶心呕吐的发生率明显高于A组,且A组比B组苏醒时间明显缩短。结论氯胺酮复合丙泊酚用于小儿麻醉效果更加安全圾效。     

Pharmacokinetics and tolerability of artesunate and amodiaquine alone and in combination in healthy volunteers

Objectives  The WHO recommends artemisinin-based combination therapies for treatment of uncomplicated falciparum malaria. At least 15 African countries have adopted artesunate plus amodiaquine as treatment policy. As no pharmacokinetic data on this combination have been published to date, we investigated its pharmacokinetic interactions and tolerability in healthy volunteers in Africa. Methods  In a randomized, three-phase, cross-over study, amodiaquine (10 mg/kg) and artesunate (4 mg/kg) were given as single oral doses to 15 healthy volunteers. Artesunate was given to all volunteers on day 0. On day 7 they received either amodiaquine or amodiaquine plus artesunate and the alternative regimen on day 28. The pharmacokinetics of artesunate and amodiaquine and their main active metabolites dihydroartemisinin and desethylamodiaquine were compared following monotherapy and combination therapy using analysis of variance. Results  Thirteen volunteers completed the study, and pharmacokinetic parameters could be determined for twelve volunteers. When given in combination, the mean AUC was lower for dihydroartemisinin [ratio 67% (95% CI 51–88%); P = 0.008] and desethylamodiaquine [ratio 65% (95% CI 46–90%); P = 0.015] when compared with monotherapy. Adverse events of concern occurred in four volunteers (27%): grade 3 transaminitis (n = 1), neutropaenia (n = 2), and hypersensitivity (n = 1). Conclusion  The total drug exposure to both drugs was reduced significantly when they were given in combination. The clinical significance of these interactions is unclear and must be studied in malaria patients. The frequency and nature of adverse events among the healthy volunteers were of concern, and suggest laboratory monitoring would be needed in malaria patients treated with artesunate plus amodiaquine.     

Arsenic induced changes in growth development and apoptosis in neonatal and adult brain cells in vivo and in tissue culture

Arsenic at a nonlethal level in drinking water consumed over a period of time has been reported to produce chronic toxicity and various types of health problems ranging from skin cancer to disturbance in memory. Neurotoxic effects have been reported in clinical cases with chronic exposure to arsenic. Physiological detoxication of arsenic occurs partially through methylation. Arsenic and its methylated derivatives are distributed in different organs and systems. The present study examined the possible interference in the neuronal development and differentiation due to the exposure to arsenic during gestation. The experiments were carried out to examine short and long term effects of arsenic on brain explants and cells grown and maintained in tissue culture system. The effects of arsenic exposure showed changes in brain cell membrane function indicated by generation and release of reactive oxygen-nitrogen intermediates. On the morphological aspect the explants' growth was reduced, ground matrix was lost and neural networking was inhibited. Cells showed signs of apoptotic changes. Arsenic toxicity may induce damage to brain cells prior to more visible clinical conditions. The deleterious effects also pass from the maternal to fetal tissue across the transplacental barrier.     

Evaluation of pharmacokinetic interactions between bicyclol and co-administered drugs in rat and human liver microsomes in vitro and in rats in vivo

1. Bicyclol is a new synthetic anti-hepatitic drug and primarily metabolized by CYP3A. The aim of this study was to evaluate the pharmacokinetic interactions between bicyclol and co-administered drugs including metformin, pioglitazone, atorvastatin, fenofibrate, Cyclosporin A (CsA), and tacrolimus in rat and human liver microsomes (RLMs/HLMs) in vitro and in rats in vivo.

2. The depletion rate of bicyclol in RLMs was significantly inhibited by 44.8% and 35.5% after preincubation with pioglitazone and fenofibrate while the metabolite formation rate of bicyclol in HLMs was inhibited by 26.1% and 23.9% after preincubation and coincubation with tacrolimus, and by 20.2% after preincubation with CsA. Conversely, preincubation and coincubation with bicyclol significantly inhibited the depletion rate of pioglitazone in RLMs by 34.1% and 27.1%, respectively, and the formation rate of para- and ortho-hydroxy atorvastatin in RLMs and HLMs by 20.6–36.2%. There were no significant pharmacokinetic interactions between bicyclol and pioglitazone in rats after a single or multiple oral treatment.

3. As the selected inhibitory drug concentrations in vitro were significantly higher than those in clinical settings and the maximum inhibition rate did not exceed 50%, the clinically significant interaction between bicyclol and these co-administered drugs in humans is predicted less likely to happen.