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1.
常云成 《家庭医药》2013,(11):78-79
几千年来,人类探寻长寿密码的行动一直都未停止。近日,有关专家组团踏上寻访中IN30位最长寿老人之路,38天时间,10个省份,破解了全国老寿星们的终极长寿密码——地气、元气、心气、神气.  相似文献   

2.
3.
3岁的贝贝患了感冒后,就一直打喷嚏、流鼻涕,家人给吃点感冒药本以为控制住了.不想药刚停了没两天,夜里就发起了烧,感冒卷土重来,而且更加严重缠缠绵绵久治不愈,后来尝试中医治疗,病情才慢慢好起来.小儿感冒发热,很多家长认为西药见效快,孩子一感冒就要把病症压下去。但是往往吃了药,症状消失了,  相似文献   

4.
张勇 《中国药店》2008,(6):78-79
北京好得快大药房的单店日均销售高居全国前列,而且销售还以不低于20%的速度在增长,这很大程度源于好得快的“1+2+X营销模式”。  相似文献   

5.
滕小春  刘海峰 《现代医药卫生》2006,22(16):2480-2481
胞膜离子交换蛋白Na^+-H^+交换泵(Na^+-H^+ exchanger,NHE)是存在于所有真核细胞的一种跨膜蛋白,该蛋白涉及细胞的多种功能。迄今为止,已克隆了8个亚型NHE的cDNA,它们构成了,脊椎动物胞膜离子转运泵的一个基因家族。在肿瘤、高血压及糖尿病等疾病中,已发现NHE1亚型的mRNA表达水平显著增高.因此,研究它们的活性调节机制,将可能为这些疾病的诊治提供新的手段。  相似文献   

6.
齐天杰  阎锡新  张鲁涛 《河北医药》2011,33(20):3045-3047
目的探讨血液CD3+CD4+/CD3+CD8+T淋巴细胞水平对非HIV感染患者发生侵袭性肺部真菌感染的影响。方法根据入选标准及诊治规范,入选IPFI组患者61例,非IPFI肺炎组患者47例及同期健康对照组体检者30例。收集记录上述患者的临床资料,观察3组病例CD3CD;T淋巴细胞百分比,CD3+CD8+T淋巴细胞百分比及CD3+CD4+/CD3+CD8+T淋巴细胞比值情况。结果白色念珠菌仍是最常见的致病真菌,占总检出菌株数的46.03%,同时本研究曲霉菌(30.16%)感染也占有相当高的比例。CD3+CD4+T淋巴细胞百分比及CD3+CD4+/CD3+CD8+T细胞比值水平,IPFI组较非IPFI肺炎组(t=5.910,P〈0.05;t=7.395,P〈0.05)及健康对照组(t=6.443,P〈0.05;t=7.428,P〈0.05)均明显下降。结论血液CD4+/CD8+T淋巴细胞水平测定有助于早期发现肺部真菌感染的发生。  相似文献   

7.
我这些年来所想所做的,就是外人看起来微不足道、不起眼的小事,将这些小事做好、做精、做透,想顾客之所想、急顾客之所急,站在顾客角度思考和服务,不仅赢得了口碑,同时也走进了顾客的心智空间。  相似文献   

8.
在历史的进程中,手杖并没有像其他一些工具一样为社会所淘汰,而是随着时代的进步逐渐演变并发展,在日常生活、医疗、运动等备方面都能为人们提供帮助,已经远远超越了“第三条腿”的作用,成了人们生活中随处可见的一部分。  相似文献   

9.
三七总皂苷对Na^+—K^+—ATP酶和Ca^2+—Mg^2+...   总被引:2,自引:0,他引:2  
  相似文献   

10.
11.

Aim:

To determine whether ginsenosides with various sugar attachments may act as active components responsible for the cardiac therapeutic effects of ginseng and sanqi (the roots of Panax ginseng and Panax notoginseng) via the same molecular mechanism triggered by cardiac glycosides, such as ouabain and digoxin.

Methods:

The structural similarity between ginsenosides and ouabain was analyzed. The inhibitory potency of ginsenosides and ouabain on Na+/K+-ATPase activity was examined and compared. Molecular modeling was exhibited for the docking of ginsenosides to Na+/K+-ATPase.

Results:

Ginsenosides with sugar moieties attached only to the C-3 position of the steroid-like structure, equivalent to the sugar position in cardiac glycosides, and possessed inhibitory potency on Na+/K+-ATPase activity. However, their inhibitory potency was significantly reduced or completely abolished when a monosaccharide was linked to the C-6 or C-20 position of the steroid-like structure; replacement of the monosaccharide with a disaccharide molecule at either of these positions caused the disappearance of the inhibitory potency. Molecular modeling and docking confirmed that the difference in Na+/K+-ATPase inhibitory potency among ginsenosides was due to the steric hindrance of sugar attachment at the C-6 and C-20 positions of the steroid-like structure.

Conclusion:

The cardiac therapeutic effects of ginseng and sanqi should be at least partly attributed to the effective inhibition of Na+/K+-ATPase by their metabolized ginsenosides with sugar moieties attached only to the C-3 position of the steroid-like structure.  相似文献   

12.

Aim:

To examine if magnesium lithospermate B (MLB), a potent inhibitor of Na+/K+-ATPase, leads to the elevation of intracellular Ca2+ level as observed in cells treated with cardiac glycosides.

Methods:

Viability of SH-SY5Y neuroblastoma cells treated with various concentrations of ouabain or MLB was measured. Intracellular Ca2+ levels were visualized using Fluo4-AM (fluorescent dye) when cells were treated with ouabain or MLB in the presence or absence of KB-R7943 (Na+/Ca2+ exchanger inhibitor) and 2-APB (IP3 receptor antagonist). Molecular modeling was conducted for the docking of ouabain or MLB to Na+/K+-ATPase. Changes of cell body and dendrite morphology were monitored under a microscope.

Results:

severe toxicity was observed in cells treated with ouabain of concentration higher than 1 μmol/L for 24 h while no apparent toxicity was observed in those treated with MLB. Intracellular Ca2+ levels were substantially elevated by MLB (1 μmol/L) and ouabain (1 μmol/L) in similar patterns, and significantly reduced in the presence of KB-R7943 (10 μmol/L) or 2-APB (100 μmol/L). Equivalent interaction with the binding cavity of Na+/K+-ATPase was simulated for ouabain and MLB by forming five hydrogen bonds, respectively. Treatment of ouabain (1 μmol/L), but not MLB (1 μmol/L), induced dendritic shrink of SH-SY5Y cells.

Conclusion:

Comparable to ouabain, MLB leads to the elevation of intracellular Ca2+ level presumably via the same mechanism by inhibiting Na+/K+-ATPase. The elevated Ca2+ levels seem to be supplied by Ca2+ influx through the reversed mode of the Na+/Ca2+ exchanger and intracellular release from endoplasmic reticulum.  相似文献   

13.

Aim:

To investigate the effect of acute insulin administration on the subcellular localization of Na+/K+-ATPase isoforms in cardiac muscle of healthy and streptozotocin-induced diabetic rats.

Methods:

Membrane fractions were isolated with subcellular fractionation and with cell surface biotinylation technique. Na+/K+-ATPase subunit isoforms were analysed with ouabain binding assay and Western blotting. Enzyme activity was measured using 3-O-methylfluorescein-phosphatase activity.

Results:

In control rat heart muscle α1 isoform of Na+/K+ ATPase resides mainly in the plasma membrane fraction, while α2 isoform in the intracellular membrane pool. Diabetes decreased the abundance of α1 isoform (25 %, P<0.05) in plasma membrane and α2 isoform (50%, P<0.01) in the intracellular membrane fraction. When plasma membrane fractions were isolated by discontinuous sucrose gradients, insulin-stimulated translocation of α2- but not α1-subunits was detected. α1-Subunit translocation was only detectable by cell surface biotinylation technique. After insulin administration protein level of α2 increased by 3.3-fold, α1 by 1.37-fold and β1 by 1.51-fold (P<0.02) in the plasma membrane of control, and less than 1.92-fold (P<0.02), 1.19-fold (not significant) and 1.34-fold (P<0.02) in diabetes. The insulin-induced translocation was wortmannin sensitive.

Conclusion:

This study demonstrate that insulin influences the plasma membrane localization of Na+/K+-ATPase isoforms in the heart. α2 isoform translocation is the most vulnerable to the reduced insulin response in diabetes. α1 isoform also translocates in response to insulin treatment in healthy rat. Insulin mediates Na+/K+-ATPase α1- and α2-subunit translocation to the cardiac muscle plasma membrane via a PI3-kinase-dependent mechanism.  相似文献   

14.

Background and purpose:

All cardiac steroids have a similar structure, bind to and inhibit the ubiquitous transmembrane protein Na+, K+-ATPase and increase the force of contraction of heart muscle. However, there are diverse biological responses to different cardiac steroids both at the cellular and at the molecular level. Moreover, we have recently shown that ouabain inhibits digoxin- and bufalin-induced changes in membrane traffic. The present study was designed to test the hypothesis that ouabain also has an inhibitory effect on cardiotoxicity induced by other cardiac steroids.

Experimental approach:

The hypothesis was tested in isolated heart muscle preparations and in an in vivo model of cardiotoxicity in guinea pigs.

Key results:

Ouabain at a low dose attenuated the toxicity induced by bufalin and digoxin in heart muscle preparations. In addition, ouabain at the low dose (91 ng·kg−1·h−1), but not at a higher dose (182 ng·kg−1·h−1), delayed the development of digoxin-induced (500 µg·kg−1·h−1) cardiotoxicity in anaesthetized guinea pigs, as manifested by delayed arrhythmia and terminal ventricular fibrillation, as well as a reduced heart rate. In addition, as observed with ouabain, the phosphoinositide 3-kinase inhibitor wortmannin (100 µg·kg−1·h−1) delayed the digoxin-induced arrhythmia in anaesthetized guinea pigs.

Conclusions and implications:

The present study demonstrates the inhibitory effect, probably through signal transduction pathways, of ouabain on digoxin- and bufalin-induced cardiotoxicity in guinea pigs. Further understanding of this phenomenon could be beneficial for increasing the therapeutic window for cardiac steroids in the treatment of chronic heart failure.  相似文献   

15.

Background and purpose:

Dopamine inhibits renal cell Na+,K+-ATPase activity and cell sodium transport by promoting the internalization of active molecules from the plasma membrane, whereas angiotensin II (ATII) stimulates its activity by recruiting new molecules to the plasma membrane. They achieve such effects by activating multiple and distinct signalling molecules in a hierarchical manner. The purpose of this study was to investigate whether dopamine and ATII utilize scaffold organizer proteins as components of their signalling networks, in order to avoid deleterious cross talk.

Experimental approach:

Attention was focused on a multiple PDZ domain protein, Pals-associated tight junction protein (PATJ). Ectopic expression of PATJ in renal epithelial cells in culture was used to study its interaction with components of the dopamine signalling cascade. Similarly, expression of PATJ deletion mutants was employed to analyse its functional relevance during dopamine-, ATII- and insulin-dependent regulation of Na+,K+-ATPase.

Key results:

Dopamine receptors and components of its signalling cascade mediating inhibition of Na+,K+-ATPase interact with PATJ. Inhibition of Na+,K+-ATPase by dopamine was prevented by expression of mutants of PATJ lacking PDZ domains 2, 4 or 5; whereas the stimulatory effect of ATII and insulin on Na+,K+-ATPase was blocked by expression of PATJ lacking PDZ domains 1, 4 or 5.

Conclusions and implications:

A multiple PDZ domain protein may add functionality to G protein-coupled and tyrosine kinase receptors signalling during regulation of Na+,K+-ATPase. Signalling molecules and effectors can be integrated into a functional network by the scaffold organizer protein PATJ via its multiple PDZ domains.  相似文献   

16.

Objective:

To study the role of Na+, K+- ATPase enzyme in the vascular response of goat ruminal artery.

Materials and Methods:

Ruminal artery was obtained in chilled aerated modified Krebs-Henseleit solution (KHS) from a local slaughterhouse and transported in ice for further processing. The endothelium intact arterial ring was mounted in a thermostatically controlled (37 ± 0.5°C) organ bath containing 20 ml of modified KHS (pH 7.4) bubbled with oxygen (95%) and CO2 (5%) under 2g tension. An equilibration of 90 min was allowed before addition of drugs into the bath. The responses were recorded isometrically in an automatic organ bath connected to PowerLab data acquisition system. In order to examine intact functional endothelium, ACh (10 μM) was added on the 5-HT (1.0 μM) - induced sustained contractile response. Similarly, functional characterization of Na+, K+-ATPase activity was done by K+-induced relaxation (10 μM-10 mM) in the absence and presence of ouabain (0.1 μM/ 0.1 mM), digoxin (0.1 μM) and barium (30 μM).

Results:

ACh (10−5 M) did not produce any relaxing effect on 5-HT-induced sustained contractile response suggesting that vascular endothelium has no significant influence on the activation of sodium pump by extracellular K+ in ruminal artery. Low concentration of Ba2+ (30 μM) (IC50: 0.479 mM) inhibited K+-induced relaxation suggesting Kir (inward rectifier) channel in part had role in K+-induced vasodilatation in ruminal artery. Vasorelaxant effect of KCl (10 μM-10 mM) in K+-free medium is also blocked by ouabain (0.1 μM and 0.1 mM) (IC50:0.398 mM and IC35: 1.36 mM), but not by digoxin (0.1 μM) (IC50 0.234 mM) suggesting that ouabain sensitive Na+, K+-ATPase isoform is present in the ruminal artery.

Conclusion:

In the goat ruminal artery functional regulation of sodium pump is partly mediated by K+ channel and ouabain sensitive Na+, K+ ATPase.  相似文献   

17.

Aim:

To determine whether replacing Mg2+ in magnesium lithospermate B (Mg-LSB) isolated from danshen (Salvia miltiorrhiza) with other metal ions could affect its potency in inhibition of Na+/K+-ATPase activity.

Methods:

Eight metal ions (Na+, K+, Mg2+, Cr3+, Mn2+, Co2+, Ni2+, and Zn2+) were used to form complexes with LSB. The activity of Na+/K+-ATPase was determined by measuring the amount of inorganic phosphate (Pi) liberated from ATP. Human adrenergic neuroblastoma cell line SH-SY5Y was used to assess the intracellular Ca2+ level fluctuation and cell viability. The metal binding site on LSB and the binding mode of the metal-LSB complexes were detected by NMR and visible spectroscopy, respectively.

Results:

The potencies of LSB complexed with Cr3+, Mn2+, Co2+, or Ni2+ increased by approximately 5 times compared to the naturally occurring LSB and Mg-LSB. The IC50 values of Cr-LSB, Mn-LSB, Co-LSB, Ni-LSB, LSB, and Mg-LSB in inhibition of Na+/K+-ATPase activity were 23, 17, 26, 25, 101, and 128 μmol/L, respectively. After treatment of SH-SY5Y cells with the transition metal-LSB complexes (25 μmol/L), the intracellular Ca2+ level was substantially elevated, and the cells were viable for one day. The transition metals, as exemplified by Co2+, appeared to be coordinated by two carboxylate groups and one carbonyl group of LSB. Titration of LSB against Co2+ demonstrated that the Co-LSB complex was formed with a Co2+:LSB molar ratio of 1:2 or 1:1, when [Co2+] was less than half of the [LSB] or higher than the [LSB], respectively.

Conclusion:

LSB complexed with Cr3+, Mn2+, Co2+, or Ni2+ are stable, non-toxic and more potent in inhibition of Na+/K+-ATPase. The transition metal-LSB complexes have the potential to be superior substitutes for cardiac glycosides in the treatment of congestive heart failure.  相似文献   

18.

BACKGROUND AND PURPOSE

Pulmonary transepithelial Na+ transport is reduced by hypoxia, but in the airway the regulatory mechanisms remain unclear. We investigated the role of AMPK and ROS in the hypoxic regulation of apical amiloride-sensitive Na+ channels and basolateral Na+K+ ATPase activity.

EXPERIMENTAL APPROACH

H441 human airway epithelial cells were used to examine the effects of hypoxia on Na+ transport, AMP : ATP ratio and AMPK activity. Lentiviral constructs were used to modify cellular AMPK abundance and activity; pharmacological agents were used to modify cellular ROS.

KEY RESULTS

AMPK was activated by exposure to 3% or 0.2% O2 for 60 min in cells grown in submerged culture or when fluid (0.1 mL·cm−2) was added to the apical surface of cells grown at the air–liquid interface. Only 0.2% O2 activated AMPK in cells grown at the air–liquid interface. AMPK activation was associated with elevation of cellular AMP : ATP ratio and activity of the upstream kinase LKB1. Hypoxia inhibited basolateral ouabain-sensitive Isc (Iouabain) and apical amiloride-sensitive Na+ conductance (GNa+). Modification of AMPK activity prevented the effect of hypoxia on Iouabain (Na+K+ ATPase) but not apical GNa+. Scavenging of superoxide and inhibition of NADPH oxidase prevented the effect of hypoxia on apical GNa+ (epithelial Na+ channels).

CONCLUSIONS AND IMPLICATIONS

Hypoxia activates AMPK-dependent and -independent pathways in airway epithelial cells. Importantly, these pathways differentially regulate apical Na+ channels and basolateral Na+K+ ATPase activity to decrease transepithelial Na+ transport. Luminal fluid potentiated the effect of hypoxia and activated AMPK, which could have important consequences in lung disease conditions.  相似文献   

19.
柴胡皂甙和甘草甜素抑制Na+,K+-ATP酶活性的构效关系   总被引:8,自引:0,他引:8  
研究在离体条件下各种单体柴胡皂甙和甘草甜素抑制Na+,K+-ATP酶活性的构效关系。实验结果表明,各种柴胡皂甙抑制Na+,K+-ATP酶活性的作用强度依次为:b1>d>b2>b4>a>b3>e>c。柴胡皂甙化学结构中的C23-OH,C16-OH及C11和C13的共轭双烯可能对其抑制活性起重要作用。甘草甜素(GL),甘草次酸(GA)和生胃酮(18-β-甘草次酸半琥珀酸双钠盐,CX)抑制Na+,K+-ATP酶活性的作用强度依次为GA≥CX>GL。研究还证明,柴胡皂甙d对Na+,K+-ATP酶的抑制为非竟争性抑制。  相似文献   

20.

Background and purpose:

Epithelial surface hydration is critical for proper gut function. However, colonic tissues from individuals with inflammatory bowel disease or animals with colitis are hyporesponsive to Cl secretagogues. The Cl secretory responses to the muscarinic receptor agonist bethanechol are virtually absent in colons of mice with dextran sodium sulphate (DSS)-induced colitis. Our aim was to define the mechanism underlying this cholinergic hyporesponsiveness.

Experimental approach:

Colitis was induced by 4% DSS water, given orally. Epithelial ion transport was measured in Ussing chambers. Colonic crypts were isolated and processed for mRNA expression via RT-PCR and protein expression via immunoblotting and immunolocalization.

Key results:

Expression of muscarinic M3 receptors in colonic epithelium was not decreased during colitis. Short-circuit current (ISC) responses to other Ca2+-dependent secretagogues (histamine, thapsigargin, cyclopiazonic acid and calcium ionophore) were either absent or severely attenuated in colonic tissue from DSS-treated mice. mRNA levels of several ion transport molecules (a Ca2+-regulated Cl channel, the intermediate-conductance Ca2+-activated K+ channel, the cystic fibrosis transmembrane conductance regulator, the Na+/K+-ATPase pump or the Na+/K+/2Cl co-transporter) were not reduced in colonic crypts from DSS-treated mice. However, protein expression of Na+/K+-ATPase α1 subunits was decreased twofold during colitis. Activation of Ca2+-activated K+ channels increased ISC significantly less in DSS colons compared with control, as did the protein kinase C activator, phorbol 12-myristate 13-acetate.

Conclusions and implications:

Decreased Na+/K+-ATPase expression probably contributes to overall epithelial hyporesponsiveness during colitis, while dysfunctional K+ channels may account, at least partially, for lack of epithelial secretory responses to Ca2+-mediated secretagogues.  相似文献   

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