不同血浆样品制备方法对芍药苷血液药物浓度测定的影响

目的比较乙腈法、高氯酸法和磷酸二氢钠酸化法三种不同的血浆样品处理方法对芍药苷血液药物浓度测定的影响,优选最佳的血浆样品处理方法。方法高效液相色谱法测定血浆样品中不同浓度的芍药苷,比较三种方法对样品中芍药苷的回收率、检测的灵敏度以及实验结果可重复性等方面的影响。结果用乙腈和高氯酸处理芍药苷浓度>50μg/ml的血浆样品时,均能得到较高的回收率;但对于芍药苷浓度<50μg/ml的血浆样品,仅高氯酸处理的样品才能得到较高的回收率;并且高氯酸处理血浆能检测的最低芍药苷血液药物浓度为0.5μg/ml,具有较好的灵敏度。结论对于检测芍药苷的血液药物浓度,用高氯酸处理血浆样品最为适合。     

Determination of chlorogenic acid in rat plasma by high performance chromatography after peritoneal administration of compound Daqingye injection

A simple and sensitive high performance liquid chromatographic method has been developed for the determination of chlorogenic acid (3-O-caffeoyl-D-quinic acid) in rat plasma and applied to its pharmacokinetic study in rats after peritoneal administration of compound Daqingye injection. Plasma samples are extracted with perchloric acid. HPLC analysis of the chlorogenic acid is performed on a C(18) reversed-phase column using methanol-water (80: 20, v/v, pH 2.8) as mobile phase with UV detector set at 327 nm. The standard curves are linear in the range of 0.200-10.0 microg/ml (r=0.9982). The inter- and intra-day precision (relative standard deviation) was less than 9% and the accuracy (relative error) was less than 10%. The limit of quantitation was 0.200 microg/ml. The plasma concentration of chlorogenic acid shows a C(max) of 7.53+/-0.52 microg/ml at 13.33+/-4.00 min with a t(1/2) of 59.10+/-5.42 min.     

HPLC分离测定大鼠血中促肝细胞生长素

选用大鼠灌胃给予促肝细胞生长素，断尾取血，血样经6％高氯酸沉淀蛋白，用高效液相色谱分离。流动相为0．05mol／L磷酸二氢钾溶液（pH=2～3），流速0．8ml／min，检测波长268nm；结果表明，血样中有促肝细胞生长素样品类似色谱指纹图。     

HPLC法测定患者血浆中氯吡格雷的羧酸代谢产物浓度

目的:建立一种简易快速的方法测定人血浆中氯吡格雷代谢产物羧酸氯吡格雷(CCA)的浓度。方法:血浆样品经6%高氯酸液-液萃取后采用高效液相色谱-紫外(HPLC-UV)法进样测定,内标为苯妥英钠,色谱柱为Hypersil ODS C18,流动相为0.05mol/L磷酸二氢钾(三乙胺调pH至5.7)-乙腈(78∶22),紫外检测波长为220 nm,流速为1.0 ml/min,柱温为50℃。结果:CCA血药浓度在0.10⁸.0μg/ml范围内线性关系良好(r=0.999 5),分析方法最低检测限为0.05μg/ml;方法回收率为99.7%8.0μg/ml范围内线性关系良好(r=0.999 5),分析方法最低检测限为0.05μg/ml;方法回收率为99.7%¹00.2%,提取回收率>75%;日内、日间RSD均小于3%,冻融稳定性RSD均小于10%(n=5)。结论:本方法简便、准确、灵敏度高,专属性和稳定性较好,适用于氯吡格雷的临床研究和药动学研究。     

高效液相色谱法测定醋氯芬酸缓释片的含量

目的：建立了高效液相色谱法测定醋氯芬酸缓释片的含量。方法：采用Zorbax SB-C18色谱柱,以乙腈－四氢呋喃－冰醋酸（25：25：50,用1．0mol/L的NaOH高pH3.5）为流动相,流速为1.0ml/min,以对羟基联苯为内标物,检测波长为275nm,结果：醋 芬酸在10．2－50．1ug/ml范围内呈良好线性（r=0.9993),平均回收率为100．3％,RSD为0．45％,结论：本法可用于该片剂的测定,操作简便,结果准确。     

高效液相色谱法测定左旋多巴／苄丝肼分散片血药浓度及其药代动力学研究

目的建立左旋多巴血药浓度的测定方法并对其分散片的人体药代动力学进行研究。方法采用反相高效液相色谱法,色谱柱为Lichrospher100C     

Pharmacokinetics and hemodynamic effects of long-term nifedipine treatment in hypertensive patients

In six patients with essential hypertension, pharmacokinetics and pharmacodynamics of nifedipine were investigated during 6 weeks of treatment. On day 1 nifedipine was infused intravenously (6.0 mg within 60 min), and on day 2 oral nifedipine treatment (20-mg tablets, twice daily) was started. Patients came to the hospital once weekly, when blood samples were taken and blood pressure and heart rate were assessed prior to tablet intake and 3 h later. After 6 weeks of oral treatment the intravenous infusion experiment was repeated. At the first intravenous nifedipine infusion a total systemic plasma clearance of 671 +/- 240 ml/min (mean +/- SD), an elimination half-life of 95 +/- 36 min, and a volume of distribution of 60.2 +/- 11.9 L were found. Protein unbound fraction of nifedipine amounted to 4.6 +/- 0.3%. After 6 weeks of oral treatment half-life was almost doubled (p less than 0.05), whereas in most patients the volume of distribution had slightly increased and systemic plasma clearance was decreased. Using a sigmoidal model, hemodynamic effects were fitted to nifedipine plasma concentrations. After 6 weeks the maximal effect of intravenous nifedipine on both systolic and diastolic blood pressures had significantly decreased. In four patients the potency had decreased considerably. During oral nifedipine treatment the mean plasma half-life was 5.8 +/- 1.0 h; trough concentration was 11.3 +/- 4.1 ng/ml and peak concentrations were 36.8 +/- 14.3 ng/ml. During chronic treatment heart rate was not significantly changed, whereas systolic and diastolic blood pressures were significantly reduced (p less than 0.02 and less than 0.01, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

Bioavailability of salvianolic acid B in conscious and freely moving rats

Salvianolic acid B is an herbal ingredient isolated from Salvia miltiorrhiza. The aim of this study was to apply an automated blood sampling system coupled to a simple liquid chromatographic system to determine the bioavailability of salvianolic acid B in stress-free rats. The plasma sample (25 microl) was vortex-mixed with 50 microl of internal standard solution (chloramphenicol 10 microg/ml in acetonitrile) to achieve protein precipitation. Salvianolic acid B in the rat plasma was separated using a reversed-phase C18 column (250 mm x 4.6 mm, 5 microm) with a mobile phase of acetonitrile-methanol-20mM NaH(2)PO(4) (adjusted to pH 3.5 with H(3)PO(4)) (20:10:70 v/v/v) containing 0.1mM 1-octanesulfonic acid, and the flow-rate of 1 ml/min. The UV detection wavelength was 286 nm. The concentration-response relationship from the present method indicated linearity over a concentration range of 0.5-200 microg/ml. Intra- and inter-assay precision and accuracy of salvianolic acid B fell well within the predefined limits of acceptability (<15%). The plasma sample of salvianolic acid B was further identified by LC-MS/MS in the negative ion mode using mass transition m/z 358.2 to the product ion m/z 196.9. After salvianolic acid B (100mg/kg, i.v.; 500 mg/kg, p.o.) was given in conscious and freely moving rats, the AUC were 5030+/-565 and 582+/-222 min microg/ml for intravenous (100 mg/kg) and oral (500 mg/kg) doses, respectively. The oral bioavailability of salvianolic acid B in freely moving rats was calculated to be 2.3%.     

高效液相色谱法测定人体5-氟尿嘧啶血药浓度

目的 :以高效液相色谱法测定人血浆中5 -氟尿嘧啶的浓度。方法 :用硫酸铵作为蛋白沉淀剂 ,血浆样品用乙酸乙酯 -异丙醇(85∶15 ,V/V )提取 ,氮气吹干 ,残留物用流动相溶解后进样。色谱柱为DiamonsilC18 柱 (4 6mm×150mm ,5μm ) ,流动相为0 01mol/LKH2PO4(pH5 5) ,流速1 5ml/min ,紫外检测波长267nm ,5 -溴尿嘧啶为内标。结果 :本法最低检测浓度为0 025μg/ml ,线性范围为0 3～10μg/ml ,日内RSD≤5 0 % (n=5) ,日间RSD≤11 5 % (n=5)。结论 :本法简便、灵敏、经济 ,可作为5 -氟尿嘧啶药代动力学研究时血药浓度的测定方法。     

Hemoperfusion-hemodialysis ineffective for paraquat removal in life-threatening poisoning?

We report on a patient treated with hemoperfusion-hemodialysis (HP-HD) for severe paraquat poisoning. This procedure was adopted since the combination of adsorption and dialysis may improve overall drug removal. On admission blood paraquat was 15.8 micrograms/ml. He received conventional treatment and combined HP-HD which started within 3 hours after ingestion of the chemical and lasted 5 hours. Blood samples were obtained during and after HP-HD. The samples during HP-HD were taken before the charcoal column, between the charcoal column and the artificial kidney and after the artificial kidney. Blood clearances of paraquat were 116 +/- 32 ml/min (n=6) for the charcoal column (HP), 90 +/- 54 ml/min (n=6) for the artificial kidney (HD) and 151 +/- 37 ml/min (n=6) for the combined systems (HP-HD). After HP-HD a limited rebound of blood paraquat level was seen. One day after admission renal and hepatic failure had developed, and the patient died after 5 days. Tissue paraquat levels (microgram/g wet tissue) were: skeletal muscle 9.4, pancreas 6.0, prostate 5.6, thyroid 4.2, lungs 4.0, bone marrow 4.0, kidney 3.1, spleen 2.9, adrenal 2.9, heart 2.8, liver 2.3, stomach and testis below 1.0. Measurements of blood levels demonstrated the efficient clearances of paraquat with HP-HD from the central (plasma) compartment. However, the present results confirmed those previously reported which suggest that the efficiency of short HP-HD in treating severe paraquat poisoning is questionable since paraquat levels in the peripheral (tissue) compartment remain elevated.     

反相高效液相色谱法测定人血浆中氯氮平浓度

目的 :以反相高效液相色谱法测定人血浆中氯氮平的浓度。方法 :血浆样品经碱化后用乙醚萃取 ,醚层用100μl0 1mol/mlKH2PO4 反萃取 ,40μl进样。色谱柱为DikmaDiamonsilC18 柱 ,保护柱为WatersNova -PakC18 柱 ,流动相为0 5%三乙胺溶液 -乙腈 (74∶26,V/V) ,流速为1ml/min ,检测波长为215nm。结果 :测定方法在0 1～20μg/ml范围内线性关系良好 ,萃取回收率在80 3%～84 8%之间 ;日内、日间精密度在3 5%～8 3 %之间 ,最低检测浓度为50ng/ml。结论 :本测定方法快速、灵敏、准确 ,适用于临床治疗药物浓度监测。     

Altered pharmacokinetics of omeprazole in cystic fibrosis knockout mice relative to wild-type mice.

The cftr(tm1Unc)-knockout (CF-KO) mouse is being evaluated as a model of increased drug clearance noted clinically in patients with cystic fibrosis (CF). This study investigated whether CF-KO mice exhibited altered omeprazole pharmacokinetics compared with wild-type mice. Clinical observations have suggested reduced responses to omeprazole in CF children, which may reflect alterations in bioavailability or clearance. Omeprazole was dosed intravenously and orally in a crossover fashion to age-matched CF-KO and wild-type male and female mice. The mean terminal half-life of approximately 6 min was found across genotype and gender groups. Blood to plasma ratio estimates for omeprazole were similar across genders and genotypes with a mean value of 0.69. Omeprazole blood clearance (Cl(b)) was significantly higher in both male (190 ml/min/kg) and female (168 ml/min/kg) CF-KO mice compared with wild-type controls of the same gender (73 ml/min/kg for males and 100 ml/min/kg for females). The distributional volume of omeprazole in CF-KO mice was also statistically higher than in control genotypes. Bioavailability estimates were similar between CF-KO and wild-type females but were unavailable for male mice, due to the large variability in plasma concentrations after oral administration and the difficulty estimating the area under the plasma curve when the terminal half-life suggested absorption rate-limited disposition. Potential mechanisms for the pharmacokinetic differences observed with omeprazole in CF-KO mice may be increased hepatic blood flow or an up-regulation of hepatic transporters. These results may provide support for using the CF-KO mouse as a model for the altered disposition of drugs in CF.     

pH-induced difference spectrophotometric methods for drug analysis. Part 2: Determination of mefenamic and flufenamic acid

On the basis of the spectral changes induced by changing the solvent medium from HCl (0.01 mol . l-1) to NaOH (0.01 mol . l-1), coefficient-difference spectrophotometric methods using the six-points quadratic order of the orthogonal polynomials have been developed. The optimum wavelength ranges were 326 to 386 nm for mefenamic acid and 322 to 382 nm for flufenamic acid, both measured at 12 nm intervals. The respective mean percentage recoveries were 100.1 +/- 0.89 over a concentration range of 0.6-2.6 mg/100 ml of mefenamic acid and 100.7 +/- 0.61 over a range of 0.2-2.4 mg/100 ml for flufenamic acid (p = 0.05). Both methods gave precise results with relative standard deviation less than 1%. Trials to adapt single wavelength difference technique as well as the cubic order of the orthogonal polynomials were also performed; their results were discussed on a statistical basis. The developed procedures have been applied to the analysis of some randomly collected market preparations and the results obtained proved suitability for application in routine analysis.     

Pharmacokinetics of triflusal and its main metabolite in rats and dogs.

The methods for determining plasma concentrations of triflusal (2-acetoxy-4-trifluoromethyl benzoic acid) that have been described, do not distinguish between the drug and its main metabolite HTB (2-hydroxy-4-trifluoromethyl benzoic acid). In the present study, we have developed a new analytical technique based on HPLC that enabled us to carry out a pharmacokinetic study of the drug and its metabolite in animals. An intravenous or oral dose of 50 mg/kg was administered to male Sprague-Dawley rats, and 15 mg/kg was administered to beagle dogs. Plasma levels of triflusal and HTB were determined. In rats, triflusal was quickly eliminated from plasma with a biological half-life (t1/2) of 2.7 min and a clearance (Cl) of 73.4 (ml/kg)/min. The elimination of HTB was much slower with a t1/2 of 21.5 h and a Cl of 5.1 (mg/kg)/h. The maximum concentration (Cmax) of triflusal in rats after an oral administration was 8.1 +/- 2.0 micrograms/ml reached between 2.5 and 10 min. The Cmax of HTB was 237.7 micrograms/ml and was achieved at 0.7 h. The bioavailability of triflusal in rats was only 10.6% while the bioavailability of HTB was more than 100% indicating an important first pass effect. In dogs the t1/2 of triflusal was 14.4 +/- 5.9 min and the Cl was 25.1 +/- 4.7 (ml/kg)/min. HTB was also eliminated very slowly with a t1/2 of 71.1 +/- 12.5 h and a Cl of 2.4 +/- 0.3 (ml/kg)/h. The Cmax of triflusal in dogs was 13.3 +/- 2.9 micrograms/ml and was reached after 19.2 +/- 6.1 min (tmax).(ABSTRACT TRUNCATED AT 250 WORDS)     

A new enzyme immunoassay for aconitine and its application to quantitative determination of aconitine levels in plasma

A reliable enzyme immunoassay (EIA) method was developed for quantitative determination of aconitine with high sensitivity and specificity. The bovine serum albumin (BSA)- and beta-galactosidase (beta-Gal) conjugates as immunogens and enzyme-labeled antigens were prepared by coupling of their proteins with succinic acid (short chain length; n=2, where n represents the number of methylene units) and hexadecanedioic acid (long chain length; n=14) hemiesters of benzoylaconine through the respective N-hydroxysuccinimide esters as intermediates. Two types of the BSA-conjugates with short and long chains were repeatedly injected into rabbits to obtain anti-aconitine antisera (As1 and As2, respectively). All combinations of beta-Gal-labeled antigens LAg1 (n=2) and LAg2 (n=14) with antisera As1 (n=2) and As2 (n=14) showed high sensitivity to aconitine in a range of 0.1-1.0 ng. Although the combination of LAg2 (n=14) with antiserum As1 (n=2) showed high specificity to aconitine, the combination of LAg2 (n=14) and As2 (n=14) was highly specific to both aconitine and mesaconitine. When aconitine was intravenously administered to rats, the aconitine concentration in their plasma remarkably decreased within the first 60 min, and then gradually declined, suggesting a two-compartment pharmacokinetic model in (V(c) 0.41+/-0.09 l/kg, V(dss) 1.7+/-0.4 l/kg, CL(tot) 10+/-2 ml/min x kg, AUC(0-4800) 2055+/-294.3 ng x min/ml). Following oral administration of aconitine to rats at two doses of 0.1 and 1.0 mg/kg b.w., the maximum plasma concentrations (C(max)) were 0.73+/-0.08 and 3.3+/-0.6 ng/ml at times of 45+/-9 and 150+/-52 min, respectively, and the AUC(0-1440) values were 130+/-4 and 1600+/-270 ng x min/ml. The bioavailability (F) of aconitine was determined to be 0.013, where only 1.3% of the aconitine administered orally was absorbed into the body fluid.     

HPLC法测定患者血浆中甲氨蝶呤的浓度

目的建立高效液相色谱法实时监测患者血浆中甲氨蝶呤浓度,为临床合理用药提供参考。方法以Agilent Eclipse XDB-C18柱（4.6×150mm,5μm）为色谱柱,流动相为醋酸（pH=2.86）-甲醇（82.5：17.5,v/v）,流速：0.8ml/min,检测波长306nm,柱温柱温：40℃,样品经高氯酸沉淀蛋白后直接进样。结果表明血浆中甲氨蝶呤的质量0.3～10.20μg/ml内线性关系良好,r=1（n=3）,检测限为0.03μg/ml。方法回收率为96.43%～99.49%,提取回收率为：77.04%～85.61%。日内和日间RSD均〈5%。结论该方法简便、准确、重复性好,适用于甲氨蝶呤血药浓度监测。     

Systemic synthesis of prostaglandin I2 following sustained infusion of angiotensin II in conscious dogs

Acute infusion of pharmacological doses of angiotensin II stimulates the release of prostaglandin I2 (PGI2), which may modulate the vasoconstrictor response. It is uncertain whether sustained small increases in the plasma concentration of angiotensin II has the same effect. To investigate this further, low doses of angiotensin II were infused into conscious sodium replete dogs for 3 h. PGI2 synthesis was assessed by measurement of a major metabolite of PGI2, 2,3-dinor-6-keto PGF1 alpha, in urine and plasma, using gas chromatography mass spectrometry. Angiotensin II infusion (15 ng/min per kg body weight) resulted in a 3-fold increase in plasma angiotensin II (50.8 +/- 5.4 to 149 +/- 11.2 pg/ml, P less than 0.01). Mean blood pressure increased (84.8 +/- 4.3 to 108 +/- 4.7 mm Hg, P less than 0.02) and renal blood flow decreased (201 +/- 46 to 127 +/- 13 ml/min, P less than 0.01) throughout the infusion. However there was no change in either the plasma concentration (11.3 +/- 2.5 to 9.1 +/- 1.0 pg/ml) or rate of urinary excretion of dinor-6-keto PGF1 alpha (1.75 +/- 0.28 to 1.85 +/- 0.41 ng/30 min) during the angiotensin II infusion. The results suggest that small sustained elevations of the plasma concentration of angiotensin II such as are likely to occur in conscious animals, do not persistently stimulate release of PGI2 in the systemic circulation.     

Salbutamol disposition and dynamics in conscious rabbits: influence of the route of administration and of the dose.

This study assessed the influence of dose and route of administration on salbutamol kinetics and hypokaliemic effect. Salbutamol plasma kinetics were studied in a first group of 6 rabbits who received 60, 800, and 60 micrograms/kg by the intravenous (iv), oral (po), and intratracheal (it) routes, respectively, at 1-week intervals. A second group of 6 rabbits received 120, 2400, and 120 micrograms/kg of salbutamol by the same three routes. Multiple blood samples were withdrawn to assay salbutamol and potassium. Following iv salbutamol (60 micrograms/kg), total plasma clearance was 82 +/- 5 ml/min per kg, apparent volume of distribution was 5.0 +/- 0.5 l/kg, and terminal half-life was 41 +/- 2 min. Similar values were estimated when 120 micrograms/kg of salbutamol was administered iv or was given po or it. The bioavailability of po and it salbutamol was approximately 1 and 20%, respectively. For the first group, the maximal decrease in plasma potassium elicited by salbutamol was 0.80 +/- 0.19, 0.48 +/- 0.22, and 0.78 +/- 0.46 mmol/l, and for the second group, maximal decrement was 1.31 +/- 0.37, 0.70 +/- 0.24, and 0.84 +/- 0.17 mmol/l for the iv, po, and it routes, respectively. Compared to salbutamol peak plasma concentrations, maximal decrease in plasma potassium appeared between 60 and 108 min later for the iv route, 90 and 25 min later for po and it routes, and for this reason, the hypokaliemic effect was not associated to salbutamol plasma concentrations. The hypokaliemic effect was dependent upon the route, e.g., po > it > iv.(ABSTRACT TRUNCATED AT 250 WORDS)     

克林沙星在大鼠体内的药代动力学和生物利用度

目的　研究克林沙星在大鼠体内的药动学和生物利用度。方法　HPLC法测定大鼠ig和iv克林沙星后的血药浓度,计算药动学参数和生物利用度。色谱柱为C₁₈柱(5μm),流动相为乙腈-0.05mol·L^-1柠檬酸三乙胺液(pH2.5)(20∶80),流速为1.0mL·min^-1,检测波长300nm。结果　克林沙星0.1-20μg·mL^-1呈良好线性关系,在大鼠体内的药动学过程符合一室模型,大鼠ig50和100mg·kg^-1后,C_max和AUC均与剂量呈正比,T_1/2与剂量无关;绝对生物利用度(F)为42%。结论　克林沙星50-100mg·kg^-1的吸收和消除呈一级动力学特征,在大鼠体内的生物利用度低。     

固相萃取结合高效液相色谱法测定人血浆中格列齐特浓度

目的建立固相萃取结合高效液相色谱法测定格列齐特血药浓度的方法。方法采用固相萃取方法对血浆样品进行前处理。色谱柱为Zirchrom,流动相为乙腈-0.2%冰醋酸(60∶40),紫外检测波长为229nm,柱温为40℃,流速为1.0ml/min,以格列吡嗪为内标测定格列齐特血药浓度。结果格列齐特检测浓度在0.1～10.0μg/ml范围内线性关系良好(r=0.9966),平均回收率为99.96%,日内、日间精密度均在10%以下。结论本方法简单,测定结果准确,干扰小,适用于格列齐特的药动学及生物利用度研究。