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31.
奶牛酮病红细胞膜上ATP酶活性变化的研究   总被引:3,自引:0,他引:3  
为了深入研究酮病的发生机理,选择荷斯坦奶牛作为实验动物,应用酮粉法和改良式水杨醛比色法随机检测分组,Ⅰ组为10头对照牛、Ⅱ组为10 头阳性牛。应用试剂盒比色法测定红细胞膜上ATPase 的活性变化。结果表明,阳性组和对照组相比,红细胞膜上ATPase的活性显著下降(P <0.05)。说明奶牛酮病影响红细胞膜上ATPase的活性变化。  相似文献   
32.
Manzamine A, a member of the manzamine alkaloids, was originally isolated from marine sponges of the genus Haliclona. It was recently shown to have activity against pancreatic cancer cells, but the precise mechanism of action remained unclear. To further our understanding of the mechanism of action of manzamine A, chemogenomic profiling in the yeast S. cerevisiae was performed, suggesting that manzamine A is an uncoupler of vacuolar ATPases. Fluorescence microscopy confirmed this effect on yeast vacuoles, where manzamine A produced a phenotype very similar to that of the established v-ATPase inhibitor bafilomycin A1. In pancreatic cancer cells, 10 µM manzamine A affected vacuolar ATPase activity and significantly increased the level of autophagosome marker LC3-II and p62/SQSTM1 as observed by western blot analysis. Treatment with manzamine A in combination with bafilomycin A1 (inhibitor of autophagosome-lysosome fusion) did not change the levels of LC3-II when compared to cells treated with bafilomycin A1 alone, suggesting that manzamine A is a potential inhibitor of autophagy by preventing autophagosome turnover. As autophagy is essential for pancreatic tumor growth, blocking this pathway with manzamine A suggests a promising strategy for the treatment of pancreatic cancer.  相似文献   
33.
Yellow catfish (Pelteobagrus fulvidraco) is an important commercial species with high aquaculture potential in China. To better understand the process of digestive functioning of gastric gland development during the larval from 1 dph (day post‐hatching) to 30 dph, real‐time PCR was used to detect and quantify the pepsinogen and H+/K+ATPase gene expression in P. fulvidraco. These data were also compared with the adult situation. The results showed that the expression of pepsinogen and H+/K+ATPase genes in P. fulvidraco larvae both started at 1 dph, though the expression level was very low until 3 dph. The quantification of pepsinogen gene expression increased significantly from 4 to 8 dph, increased fluctuantly from 8 to 23 dph and rose sharply from 23 to 30 dph. In comparison with adult fish, there were no significant differences with larvae at 5 and 23 dph. However, data of 10 and 30 dph larvae were obviously higher than those of adult group. H+/K+ATPase gene expression increased linearly from 1 to 30 dph. However, it was significantly lower than that of adult. The results show that P. fulvidraco larvae have an earlier functional stomach, though the function of the stomach is still not perfect. There is a gradual acidification environment within the stomach during the P. fulvidraco larvae development. Based on these results, we suggest that the weaning time for P. fulvidraco larvae would be much better after 23 dph.  相似文献   
34.
AIM: To investigate the effects of Xinkang recipe on myocardial miR-25-3p expression and sarcoplasmic reticulum calcium ATPase 2a (SERCA2a) activity in heart failure rats. METHODS: Male SD rats were randomly divided into normal group, sham group, model group, Xinkang recipe group (Xinkang group), and captopril group. The heart failure rat model was induced by intraperitoneal injection of doxorubicin. Distilled water, Xinkang recipe and captopril were administrated by gastric gavage for 35 d, respectively. The indexes of cardiac function and plasma level of brain natriuretic peptide (BNP) were measured. The SERCA2a activity was determined by the inorganic phosphorus method. The myocardial protein expression of SERCA2a and phospholamban (PLB) was detected by Western blot. The myocardial expression of miR-25-3p was detected by stem-loop RT-qPCR. RESULTS: Cardiac output (CO), left ventricular fractional shortening (LVFS) and left ventricular ejection fraction (LVEF) in Xinkang group and captopril group were significantly higher while the plasma levels of BNP were significantly lower than those in model group (P<0.01). The myocardial expression levels of miR-25-3p in Xinkang group and captopril group were significantly lower while the myocardial protein le-vels of SERCA2a and PLB were significantly higher than those in model group (P<0.01). The SERCA2a/PLB ratio and SERCA2a activity in Xinkang group were significantly higher than those in model group (P<0.05), and no significant change was observed between captopril group and model group. CONCLUSION: Xinkang recipe therapy may improve cardiac function in heart failure rats, which may be related to inhibiting the expression of miR-25-3p, increasing the SERCA2a/PLB ratio and enhancing SERCA2a activity in the myocardium.  相似文献   
35.
 通过静脉注射的方法研究了大肠杆菌内毒素(ET)对山羊红细胞膜和肝粒体膜损伤的膜Ca2+-ATP酶活性的变化及654-2(山莨菪碱)的保护效应。结果表明,ET处理组(ⅱ组)在1h,3h红细胞膜Ca2+-ATP酶活性高于对照组(iv组)(p<0.05),5h有下降趋势且持续到9h.12h开始回升并低于iv组(p<0.01,p<0.05).654-2处理组(ⅲ组),Ca2+-ATP酶活性除在9h、12h与iv组,在3h与ⅱ组差异不显着(p>0.05)外,均高于iv组和ⅱ组(p<0.01,p<0.05).在肝线粒体中,ⅱ组Ca2+-ATP酶活性在5h、12h均低于iv组和ⅱ组(p<0.05,p<0.01),ⅲ组Ca2+-ATP酶活性均高于iv组,但12h与iv组差异不显着(p>0.05).结果提示,ET具有诱导膜Ca2+-ATP酶活性先激活后顿抑的效应,而654-2有明显保护膜Ca2+-ATP酶活性的作用。  相似文献   
36.
以抗旱性不同的荔枝实生幼苗为试验材料,研究了水分胁迫对荔枝实生幼苗叶片质膜透性和各细胞器中Na+-K+ATPase活性的影响及其与抗旱性的关系,结果表明:(1)Na+—K+ATPase在荔枝实生幼苗叶片中的定位是细胞溶质占总活性的80.1%~82.32%,线粒体占13.34%~15.25%,叶绿体占4.34%~4.63%,品种间差异不明显。(2)叶片相对含水量随胁迫程度的增加而减少,抗旱性强的东刘1号下降的幅度小于抗旱性弱的陈紫;质膜相对透性随胁迫程度的增加而增加,抗旱性强的品种增加的幅度小于抗旱性弱的品种。(3)水分胁迫后第4天,各细胞器中Na+-K+ATPase活性均显著增加,抗旱性强的品种增加的幅度大于抗旱性弱的品种;8d后,抗旱性强的品种线粒体和叶绿体中Na+-K+ATPase继续升高,细胞溶质中Na+-K+ATPase呈下降趋势,但仍高于对照,而抗旱性弱的品种所有细胞器中Na+-K+ATPase的活性均低于对照。  相似文献   
37.
溴氰菊酯对草鱼鱼种脑AchE及ATP酶活性的影响   总被引:10,自引:0,他引:10  
本试验研究了溴氰菊酯对草鱼鱼种的急性效应以及溴氰菊酯对草鱼鱼种脑AchE及ATP酶活性的影响。结果表明,溴氰菊酯对规格Ⅰ(平均体重8.21g)、规格Ⅱ(平均 重66.6g)草鱼鱼种96h半数致死浓度(96hLC50)分别为2.16μg/L、4.26μg/L,95%置信区间分别为1.93 ̄2.42μg/L、3.82 ̄4.75μg/L,离体条件下对草鱼种脑Mg^2+-ATP酶活性抑制显著,呈一定的浓度  相似文献   
38.
Euryhaline fish, such as the Bullseye puffer Sphoeroides annulatus (Jenyns 1842), experience sudden salinity changes in their natural environment, which is more common than the exception, so they must adapt to survive and cope with extreme salt conditions. Therefore, Bullseye puffer juveniles were exposed to short‐term stress (39 hr) by fluctuating salinity conditions (41, 35, 29, 23, 17, 11, 5, 11, 17, 23, 29, 35, 41 psu) with a 3‐hr interval between each point at 26 ± 1ºC in a respirometer chamber and acclimation reservoirs. Responses to oxygen consumption rate (OCR: 23–35 mg O2 h–1 kg–1), ammonium excretion rate (AER: 1–1.85 mg NH4+ h?1 kg?1), oxygen‐nitrogen atomic ratio (O:N 17–30), osmoregulatory pattern (blood osmotic pressure from 342.4 to 332.8 mmol/kg) and changes in expression levels of Na+/K+ATPase in the gills (higher values at higher salinities) were measured. Although some signs of stress were detected below the iso‐osmotic point (11.4 psu), the puffer fish is a strong euryhaline fish that survives under these conditions. Nonetheless, it could recover when salinity returned to the initial acclimation point because Sphoeroides annulatus is able to live in a wide range of environments with wide natural salinity fluctuations; thus, a common practice in aquaculture has been to expose fish to low salinity for several reasons discussed in this study. This capacity reveals its high plasticity to saline adaptation from 41 to 5 psu an up from 5 to 41 psu, all in less than 2 days.  相似文献   
39.
为寻找防治枸杞蚜虫的适用药剂,采用玻璃管药膜法,测定了4种拟除虫菊酯类杀虫剂对枸杞蚜虫的毒力及对其三磷酸腺苷酶(ATPase)和谷胱甘肽S-转移酶(GSTs)活性的影响。结果表明:枸杞蚜虫对联苯菊酯最敏感,LC50值为4.34 mg/L;氯菊酯、高效氯氰菊酯和甲氰菊酯的LC50值分别为17.08、40.50和184.84 mg/L。4种杀虫剂对枸杞蚜虫两种ATPase活性均有抑制作用,药剂浓度为1×10-4mol/L时,4种药剂对Na+-K+-ATPase活性的抑制率均高于对Ca2+-M g2+-ATPase的抑制率,其中对Na+-K+-ATPase活性的抑制率从高到低依次为:联苯菊酯高效氯氰菊酯氯菊酯甲氰菊酯,而对Ca2+-M g2+-ATPase的抑制率则是联苯菊酯最高(46.41%),高效氯氰菊酯最低(33.04%)。4种药剂对枸杞蚜虫GSTs活性的影响差异较大:联苯菊酯在低浓度时对GSTs具有诱导作用,高浓度时则表现为一定的抑制作用;不同浓度高效氯氰菊酯和氯菊酯对GSTs活性均表现为抑制作用,抑制率最高达85.02%;而甲氰菊酯处理后GSTs的活性则升高了193.07%~249.96%。  相似文献   
40.
为了探讨ATP合酶α亚基和腺嘌呤磷酸核糖基转移酶(APRT)与温敏雄性不育系BNS育性的联系,利用荧光实时定量PCR方法,在花药发育的4个重要时期(四分体期、单核期、二核期和三核期),定量检测ATP合酶α亚基和APRT相关基因在不育及可育条件下花药中的mRNA表达水平。不育条件下,ATP合酶α亚基基因从四分体到二核期表达量持续下降,与可育株相比在单核期表达量显著下降;APRT1在4个时期的表达量低于其在相应可育条件下的表达量,而APRT2基因在BNS不育和可育条件下维持较低的表达水平。APRT相关基因表达量在三核期均有较显著提高,且可育条件下比不育条件下提高更明显。因此认为,ATP合酶α亚基基因与BNS育性转换密切正相关,APRT基因在三核期转录水平的变化与BNS育性转换有一定关系。  相似文献   
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