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1.
目的:研究普伐他汀在大鼠小肠的吸收情况。方法:采用大鼠在体小肠回流实验装置,利用HPLC紫外检测的方法测定肠循环液中酚红和普伐他汀的含量。采用XTerra@MS C-18色谱柱(5μm,150mm×2.1 mm.ID),流动相为3.5 mmol/L磷酸二氢钠溶液—乙腈(70:30,用磷酸调至pH 3.0),流速为0.2ml/min;结果:普伐他汀在大鼠小肠全肠段的吸收速率常数和吸收百分率分别为0.110±0.023(h~(-1))和18.21±2.50%。普伐他汀在小肠中吸收量与时间呈线性关系,但吸收速率较低。结论:普伐他汀可以通过增加药物的脂溶性,进而提高药物的生物利用度。 相似文献
2.
摘要 目的:从血流变和抑制炎症因子角度探讨白芷冰片的抗皮肤炎症作用及机制。方法:将60只SD大鼠随机分为 6 组: 正常组、模型组、复方醋酸地塞米松乳膏组、白芷组、冰片组和白芷冰片合用组。除正常组外,其余各实验组均使用角叉菜胶注射足底建立足皮下炎症模型。建模成功1 h后每组按设计分别在致炎处涂抹各组药物,给药4h后使用激光多普勒血流成像系统检测各组大鼠足趾血流变化,并测量足趾肿胀度,建模4 h后取炎症组织,以Elisa法检测肿胀足组织中SOD、HIS、MDA、PGE2、PGD2、COX-2以及IL-6、IL-1β、IL-8、IL-10的水平。结果:与正常组比,炎症模型组的足趾肿胀率、血流变显著增加;各给药组与模型组比较足趾肿胀率明显降低,各给药组对血流变影响差异显著,其中白芷对末梢微循环的作用明显,而冰片对足趾枝干血流变影响更显著,合用后对总体血流变有改善作用;相关细胞因子结果显示,模型组除SOD外,其余HIS、MDA、PGE2、PGD2、COX-2、IL-6、IL-1β、IL-8、IL-10显著性升高,白芷、冰片及合用组与模型组比较,各项指标因子均有不同程度的改善,其中冰片对SOD和HIS作用较弱,白芷与合用组可明显降低PGD2、COX-2、IL-6、IL-1β、IL-8指标( P < 0.05 );白芷、冰片及合用组对IL-10无明显作用。结论:白芷联合冰片对角叉菜胶诱导的急性炎症有明显的抗炎治疗作用,可显著降低水肿反应,抑制微循环扩张引起的血流变增加,其机制可能与PGE2、COX-2以及多种白介素有关。 相似文献
3.
为了考查白及有效部位在肠道的可吸收成分及其代谢特征。基于在体肠灌流模型,采用超高效液相色谱-四极杆-飞行时间质谱仪(UPLC-Q-TOF/MS)对收集到的健康SD大鼠循环肠灌流液、血清、胆汁进行分析检测,并结合对照品、质谱碎片信息和Masslynx V4.1工作站中的Single Mass Analysis功能,初步推测吸收和代谢产物的结构式。在大鼠血清和胆汁中,初步鉴定出1,4-二[4-(葡萄糖氧)苄基]-2-异丁基苹果酸、4-(葡萄糖氧)苄基]-2-异丁基苹果酸酯、α-异丁基苹果酸酯原型产物。在大鼠循环肠灌流液、血清和胆汁中,共鉴定出4-(葡萄糖氧)苄基]-2-异丁基苹果酸酯的脱糖后硫酸化代谢产物和二氢菲5的葡萄糖醛酸化代谢产物,其代谢产物主要生水解和葡萄糖醛酸化反应。该方法初步探究了白及有效部位在大鼠循环肠灌流液中可吸收成分和代谢特征,为阐释白及药材的药效物质基础提供实验依据。 相似文献
4.
为研究白及提取物中4-(葡萄糖氧基)-肉桂酸葡萄糖氧基苄酯(B12)、2-异丁基苹果酸(B6)、1-[4-(葡萄糖氧)苄基]-2-异丁基苹果酸酯(B17)、1,4-二[4-(葡萄糖氧)苄基]-2-异丁基苹果酸酯(B14)、二氢菲1(B19)和1,4-二[4-(葡萄糖氧)苄基]-2-异丁基苹果酸酯-2-[4-O-肉桂酰基-6-O-乙酰基]葡萄糖苷(B23)6个成分在大鼠小肠中的吸收动力学特性。实验采用大鼠离体外翻肠囊模型考察各成分在不同浓度、不同肠段的吸收特性,建立超高效液相色谱-三重四极杆串联质谱联用仪(UPLC-MS/MS)法测定各成分含量,计算累计吸收量和吸收速率常数。结果表明,除B6成分的低浓度外,各成分在不同浓度、不同肠段下均表现为线性吸收,其回归相关系数(R)均达到0.9以上,符合一级吸收速率,且吸收速率常数随着浓度的增加而增加,提示各成分吸收机制为被动吸收;在同一浓度下不同肠段的总体吸收趋势为十二指肠的吸收要大于回肠、结肠和空肠。综上,白及提取物中6种成分在小肠中均有吸收,但小肠对各成分的吸收具有选择性。本研究可为白及提取物的药物临床开发,确定药物剂型方面提供了一定的实验参考。 相似文献
5.
摘要 目的:从皮下血流变和炎性因子表达的角度,研究川芎白芷对过敏性皮炎组织的干预作用。方法:将60只雄性纯白豚鼠随机分为正常组、模型组、白芷组、川芎组、川芎白芷合用组和阳性药组。除正常组外,其余各实验组均使用2.4-二硝基氯苯法建立变应性接触性皮下炎症模型。建模成功后每组按设计分别在致炎各处涂抹各组药物,末次给药4 h后使用激光多普勒血流成像系统检测各组豚鼠患侧耳血流变化,取各实验组豚鼠耳组织,制备HE染色的病理切片,并使用酶联免疫吸附试验(ELISA)法检测耳组织中炎症指标因子IL-1β、TNF-α、LTB4、LTD4、PGE2和PGD2的水平。结果:与正常组比,致敏模型组的耳枝干与末端血管血流急剧增加,各给药组与模型组比较耳血管血流变明显降低,其中川芎白芷合用对炎症组织枝干血管血流影响最显著;模型的相关炎性因子水平均显著升高,各给药组炎症因子指标显著下降,LTB4、LTD4、PGD2、PGE2水平下降。川芎组与白芷组相比,抑制白细胞三烯指标LTB4、LTD4的作用更显著,白芷在IL-1β、IL-8作用较明显,川芎白芷合用组的作用优于川芎和白芷单用组。结论:川芎白芷对急性皮下炎症模型有治疗作用,可抑制组织中炎症反应,减少前列腺素类及白三烯类物质的释放,改善炎症引起的血流变反应。川芎白芷对皮下急性炎症的作用机制有差别,在抑制白细胞三烯类和白介素类炎症介质过程中有协同配伍效果。 相似文献
6.
目的:探讨炎症性肠病患者的自主神经功能状态。方法:选取炎症性肠病(IBD)患者60例作为观察组,包括活动期溃疡性结肠炎(UC)37例,活动期克罗恩病(CD)23例,同期健康体检者50例作为对照组。交感神经功能采用握力试验以及卧立位血压差的方式进行检查;迷走神经功能则采用卧立位心率变化和Valsalva动作反应指数检查方法。结果:(1)观察组卧立位心率变化均值明显低于对照组,其中溃疡性结肠炎和克罗恩病心率变化均值均明显低于对照组,差异有统计学意义(P0.05);溃疡性结肠炎与克罗恩病心率变化均值差异无统计学意义(P0.05);溃疡性结肠炎和克罗恩病Valsalva动作反应指数与对照组相比差异无统计学意义(F=1.06,P0.05)。(2)观察组卧立位血压差均值明显高于对照组,握力试验的血压反应均值明显低于对照组,溃疡性结肠炎和克罗恩病卧立位血压差均值均明显低于对照组,握力试验的血压反应均值均明显低于对照组差异有统计学意义(P0.05);而溃疡性结肠炎和克罗恩病卧立位血压差均值及血压反应均值比较均无统计学差异。结论:炎症性肠病患者存在自主神经功能紊乱,交感神经功能增强而迷走神经功能相对减弱。 相似文献
7.
目的:本研究以模式小鼠C57BL为对象,研究小鼠在衰老过程中不同组织器官内源性亚精胺含量的变化。方法:利用高效液相色谱检测小鼠心脏和肝脏组织中亚精胺含量,进一步应用qRT-PCR以及Western blot检测在衰老过程中,不同组织器官中亚精胺生物合成途径的关键基因表达变化,利用亚精胺处理细胞检测DNA损伤应答能力。结果:随着衰老的发生心脏(199.09±17.12)和肝脏组织(168.92±5.12)中亚精胺含量显著降低,分别为78.01±13.52、62.05±6.73,差异有统计学意义(P0.05);不同组织器官中亚精胺生物合成途径的关键基因Odc、Srm、Amd1的表达随衰老的发生明显下调,并且伴随着DNA损伤应答障碍;利用亚精胺处理细胞,能够增强细胞对DNA损伤的应答反应。结论:衰老的小鼠中内源性亚精胺含量降低,并且其合成途径的关键基因转录水平降低,导致细胞对DNA损伤应答能力减弱,从而加速机体衰老进程。 相似文献
8.
目的:建立超高效液相色谱法(UPLC)测定麻黄中l-麻黄碱和d-伪麻黄碱含量的方法,为麻黄药材质量评价提供依据。方法:UPLC测定麻黄碱色谱柱为Waters Acquity BEH-C_(18)(2.1 mm×50 mm, 1.7μm);检测波长:214 nm;流动相为0.15%氨水水溶液(A)和乙腈(B),梯度洗脱(0.0~4.0 min,5%B→55%B;4.0~4.1 min,55%B→95%B;4.1~4.7 min,95%B;4.7~4.8 min,95%B→5%B;4.8~5.0 min,5%B),流速:0.7mL/min;柱温:25℃。结果:l-麻黄碱和d-伪麻黄碱分别在12.50~500.00μg/mL和10.50~420.00μg/mL范围内具有良好的线性关系,相关系数均为0.9999,UPLC方法测定l-麻黄碱和d-伪麻黄碱的回收率分别为101.99%和98.68%。应用UPLC方法测定麻黄药材中的l-麻黄碱和d-伪麻黄碱的含量,麻黄药材两者含量分别为0.80%和0.18%。结论:与常规HPLC测定l-麻黄碱和d-伪麻黄碱含量方法比较,本文所用方法测定结果更加准确、全面、且重复性好,能够快速测定麻黄药材中的l-麻黄碱和d-伪麻黄碱的实际含量;并且对麻黄碱及相关物质的测定有一定的指导意义。 相似文献
9.
近年来,体外循环术后所引起的肠道功能改变及反映肠损伤的相关炎性介质变化越来越受到人们的关注。当肠屏障发生损害时,将会导致肠道内细菌移位、大量毒素及炎性因子释放,产生系统性炎症反应,进而引起脑、肺、肝、肾等多脏器功能衰竭。肠神经胶质细胞(EGCs)作为肠神经系统的重要组成部分,具有保护肠屏障功能及调节肠神经系统活动的作用。基础研究已证实,肠神经胶质细胞可作为肠屏障功能保护的相应靶点,通过激活EGCs的α7n Ach R来减轻肠屏障损伤所致的炎性反应。本文通过对近年体外循环所致肠屏障功能损伤机制和肠神经胶质细胞特点及其相关性的研究进展作一综述,从而为临床寻求防治肠损伤措施提供理论依据。 相似文献
10.
摘要:病毒感染和环境污染等使得淋巴瘤的发病率逐年升高,早期诊断和精准治疗具有十分重要的临床意义。外泌体是一种脂质双层膜结构的微小囊泡,介导了细胞间交流和信息交换。近几年许多研究证实外泌体是淋巴瘤的发生、进展和耐药的重要机制。外泌体内核酸和小分子可用于淋巴瘤的早期诊断和预测患者预后。材料学修饰可显著增强外泌体治疗的靶向性和治疗效能。本文总结了外泌体生物学特性、分离和鉴定方法、与肿瘤相关性、及其在淋巴瘤中的研究进展,为淋巴瘤的预警和治疗提供参考。 相似文献
11.
为寻找更加有效的抑菌杀菌药物,本研究利用琼脂平板打孔法和倍比稀释法评价川白芷不同溶剂萃取物对金黄色葡萄球菌、大肠杆菌、铜绿假单胞菌以及肺炎克雷伯氏菌的抗菌活性;特别是通过对铜绿假单胞菌毒力表型的影响研究考察该药物对病菌群体感应是否具有抑制作用。研究结果表明:川白芷提取液对四种细菌均有不同程度的抑制效果,且随提取物浓度增大抑制效果增强;进一步分离发现,三氯甲烷、乙酸乙酯和正丁醇提取物对四种细菌均有一定的抑制效果,其中乙酸乙酯萃取物的抑菌效果最佳;对铜绿假单胞菌的四种毒力表型的影响研究结果表明川白芷具有抑制铜绿假单胞菌群体感应的能力。试验表明川白芷的活性成分可以作为一种新型的群体感应抑制剂,其具有抑制多种细菌能力的同时不易产生耐药性,表明白芷这一传统中草药在现代医疗中具有较好的应用潜力。 相似文献
12.
白芷乙醇提取物镇痛作用研究 总被引:1,自引:0,他引:1
目的:观察白芷乙醇提取物(EEAD)的镇痛作用。方法:各组小鼠连续灌胃不同剂量的白芷乙醇提取物3d,末次给药后1 h。以热板致痛法、醋酸扭体法为疼痛模型,生理盐水为阴性对照药,阿司匹林为阳性对照药,考察白芷乙醇提取物的镇痛作用。结果:白芷提取物可显著延长小鼠热板反应的潜伏期,及扭体反应出现的时间。结论:白芷乙醇提取物镇痛作用明确。 相似文献
13.
Abstract: The effect of l -glutamate on the adrenergic-stimulated release of melatonin in the rat pineal gland was examined using an in vitro perfusion system. l -Glutamate by itself had no effect on melatonin secretion whereas l -glutamate administered prior to (–)-isoproterenol (β-adrenergic agonist) and l -phenylephrine (α-adrenergic agonist) inhibited melatonin production by 42%. l -Glutamate did not inhibit melatonin secretion when glands were stimulated with (–)-isoproterenol alone. d -Glutamate, as well as the l -glutamate agonists kainate, N -methyl- d -aspartate, quisqualate, and trans -1-aminocyclopentane-1, 3-dicarboxylic acid, had no effect on the (–)-isoproterenol-and l -phenylephrine-stimulated secretion of melatonin, which suggests that the inhibitory effects of glutamate are not mediated via any of the known glutamate receptor subtypes. The possibility that l -glutamate may be converted to another neuroactive compound (GABA) prior to the addition of (–)-isoproterenol and l -phenylephrine is suggested by the observation that simultaneous administration of l -glutamate with (–)-isoproterenol and l -phenylephrine did not inhibit melatonin production. 相似文献
14.
Mechanisms of Sodium Transport at the Blood-Brain Barrier Studied with In Situ Perfusion of Rat Brain 总被引:1,自引:0,他引:1
Abstract: The mechanism of unidirectional transport of sodium from blood to brain in pentobarbital-anesthetized rats was examined using in situ perfusion. Sodium transport followed Michaelis-Menten saturation kinetics with a V max of 50.1 nmol/g/min and a K m of 17.7 m M in the left frontal cortex. The kinetic analysis indicated that, at a physiologic sodium concentration, ∼26% of sodium transport at the blood-brain barrier (BBB) was carrier mediated. Dimethylamiloride (25 µ M ), an inhibitor of Na+ /H+ exchange, reduced sodium transport by 28%, whereas phenamil (25 µ M ), a sodium channel inhibitor, reduced the transfer constant for sodium by 22%. Bumetanide (250 µ M ) and hydrochlorothiazide (1.5 m M ), inhibitors of Na+ -K+ -2Cl− /NaCl symport, were ineffective in reducing blood to brain sodium transport. Acetazolamide (0.25 m M ), an inhibitor of carbonic anhydrase, did not change sodium transport at the BBB. Finally, a perfusate pH of 7.0 or 7.8 or a perfusate P co 2 of 86 mm Hg failed to change sodium transport. These results indicate that 50% of transcellular transport of sodium from blood to brain occurs through Na+ /H+ exchange and a sodium channel in the luminal membrane of the BBB. We propose that the sodium transport systems at the luminal membrane of the BBB, in conjunction with Cl− /HCO3 − exchange, lead to net NaCl secretion and obligate water transport into the brain. 相似文献
15.
Weiyin Huang Shuang Chen Lin Sun Hubin Wwang Hongqun Qiao 《Saudi Journal of Biological Sciences》2022,29(4):2247-2252
BackgroundThe aim of this work is to investigate the intestinal permeability of lamivudine and explore its absorption mechanism.MethodCaco-2 cells monolayer and single-pass intestinal perfusion (SPIP) were selected for the investigation of lamivudine under different conditions, such as different concentration, absorption time, bidirectional transportation, and transportation with efflux transporters inhibitor. The concentration of lamivudine both in Caco-2 cells monolayer samples and SPIP samples was detected by HPLC-UV. Then the permeability parameters were calculated.ResultsThe established HPLC-UV method reach the requirements for detection. There is no statistically difference between absorption parameters of lamivudine both in Caco-2 cells monolayer and SPIP (P > 0.05) under different dose groups. After transportation with efflux transporters inhibitor, the efflux rate of lamivudine in three dose groups was significantly decreased from 2.67, 2.59 and 2.59 to 1.78, 1.61, and 1.81 respectively. Lamivudine exhibits an absorption mechanism of passive diffusion.ConclusionThe absorption of lamivudine may be related to efflux transporters. In addition, lamivudine is a moderate-permeability drug in Biopharmaceutics Classification System. 相似文献
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《Chirality》2017,29(1):26-32
The purpose of this study was to compare intestinal permeability between enantiomers of 2‐(2‐hydroxypropanamido) benzoic acid ((R )‐/ (S )‐ HPABA), a marine‐derived antiinflammatory drug, using an in situ single‐pass intestinal perfusion (SPIP) model in rats. Concentrations, isolated regions of small intestine, and p ‐glycoprotein (P‐gp) inhibitor were performed to investigate their influences on the intestinal absorption of (R )‐/ (S )‐ HPABA. In addition, a molecular docking method was performed to illustrate our prediction. The absorption rate coefficients (K a ) and permeability values (P eff ) of (R )‐/ (S )‐ HPABA were calculated. The permeability of (S )‐HPABA was significantly (P < 0.01) higher than that of (R )‐HPABA in jejunum, and ileum permeability of (R )‐/ (S )‐ HPABA appeared best in ileum; the investigated concentrations ranged from 20 to 80 μg/mL, K a and P eff values of (R )‐/ (S )‐ HPABA increased linearly; in the presence of P‐gp inhibitor (verapamil), P eff values of two enantiomers were increased significantly; and the effect of P‐gp on absorption of (R )‐HPABA is stronger than that of (S )‐HPABA in ileum segment. Based on these results, carrier‐mediated transport or passive transport combined with carrier‐mediated transport seems to be the mechanism for intestinal absorption of (R )‐/ (S )‐ HPABA, and (R )‐/ (S )‐ HPABA may be recognized as the P‐gp substrate. In addition, the intestinal permeability of (S )‐HPABA is higher than that of (R )‐HPABA. 相似文献
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Gerbil forebrains were frozen in situ to inactivate the tissues, and 1,2-diacylglycerols were first measured quantitatively by HPLC. Although 1,2-diacylglycerols were completely recovered from the HPLC column, the control amount of 1,2-diacylglycerol in gerbil forebrain was only 79.6 nmol/g wet weight, which is about one-fourth of that previously reported for gerbil brain inactivated by liquid N2 after decapitation instead of in situ freezing. The fatty acid composition of 1,2-diacylglycerols in gerbil forebrain was first reported and the control 1,2-diacylglycerols were richer in palmitic acid than in stearic acid or arachidonic acid, which is rather different from the data previously reported for mouse or rat brain obtained by decapitation and analyzed by traditional TLC methods. The amount of 1,2-diacylglycerol increased by 82.9% in gerbil forebrain during 5 min of ischemia induced by bilateral carotid ligation. Arachidonic acid and stearic acid were abundant in the 1,2-diacylglycerols produced by 5 min of ischemia. Thus we were able to obtain accurate values of the amount and the fatty acid composition of 1,2-diacylglycerols in gerbil forebrains using HPLC and in situ freezing technique. 相似文献
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