scholarly journals Cell Membrane Surface Potential (ψ0) Plays a Dominant Role in the Phytotoxicity of Copper and Arsenate

2008 ◽  
Vol 148 (4) ◽  
pp. 2134-2143 ◽  
Author(s):  
Peng Wang ◽  
Dongmei Zhou ◽  
Thomas B. Kinraide ◽  
Xiaosan Luo ◽  
Lianzhen Li ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Surface Potential ◽  
Dominant Role ◽  
Membrane Surface ◽  
Cell Membrane Surface

scholarly journals What role does cell membrane surface potential play in ion-plant interactions

2009 ◽  
Vol 4 (1) ◽  
pp. 42-43 ◽  
Author(s):  
Peng Wang ◽  
Dong-Mei Zhou ◽  
Lian-Zhen Li ◽  
Dan-Dan Li
Keyword(s):  
Cell Membrane ◽  
Surface Potential ◽  
Membrane Surface ◽  
Plant Interactions ◽  
Cell Membrane Surface

Copper and nickel uptake and accumulation, and their effects on redox and electrical potentials of hepatopancreatic cells of Oniscus asellus Linnaeus (Porcellionidae, Isopoda)

1990 ◽  
Vol 68 (4) ◽  
pp. 651-655 ◽  
Author(s):  
M. A. Alikhan ◽  
V. Storch
Keyword(s):  
Catalytic Activity ◽  
Cell Membrane ◽  
Membrane Surface ◽  
Dry Weight ◽  
Body Tissue ◽  
Electrical Potentials ◽  
Nickel Uptake ◽  
Membrane Bound ◽  
Total Body ◽  
Cell Membrane Surface

Highest tissue Cu concentrations (1728 μg∙g dry weight−1) in whole Oniscus asellus, reared for 7 days on carrot powder containing 50 μg Cu∙g dry weight−1, 10 μg Ni∙g dry weight−1, or a mixture of 50 μg Cu and 10 μg Ni∙g dry weight−1, were observed in isopods on 50 μg Cu∙g dry weight−1, and lowest (917 μg∙g dry weight−1) in those on 10 μg Ni∙g dry weight−1. Highest Ni concentrations (277 and 272 μg∙g dry weight−1) were present in isopods fed on a mixture of 50 μg Cu and 10 μg Ni∙g dry weight−1 and 10 μg Ni∙g dry weight−1, respectively, and lowest (201 μg∙g dry weight−1) in those on 50 μg Cu∙g dry weight−1. Of the total body-tissue Cu, 8–66% was contained in membrane-bound vesicles of hepatopancreatic S-cells, and 73–89% of Ni was present inside the lumen and within S-cells of the hepatopancreas. The presence of Ni in the diet appeared to adversely affect the absorption and hepatopancreatic storage of Cu. Copper slightly enhanced, and nickel drastically reduced, the hepatopancreatic redox (= catalytic activity) and cell-membrane surface potentials. The significance of these findings is discussed.

Relationship between serum sialic acids, sialic acid-rich inflammation-sensitive proteins and cell damage in patients with acute myocardial infarction

2006 ◽  
Vol 44 (2) ◽  
Author(s):  
Selma Süer Gökmen ◽  
Cemal Kazezoğlu ◽  
Bendigar Sunar ◽  
Fatih Özçelik ◽  
Özgül Güngör ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Sialic Acid ◽  
Cell Membrane ◽  
Cell Damage ◽  
Membrane Surface ◽  
Elevated Serum ◽  
Sialic Acids ◽  
Cell Membrane Surface

AbstractThe role of sialic acid (SA) in the pathogenesis of atherosclerosis and as a predictor of cardiovascular events has attracted much attention in recent years. However, most studies investigating the role of total and lipid-bound sialic acids (TSA and LSA) in the pathogenesis of atherosclerosis lack information on the reason for the elevated SA concentrations in coronary heart disease and myocardial infarction. Since the inflammation-sensitive proteins are glycoproteins with SA residues, an increase in their levels due to some type of acute-phase reaction or inflammation could be responsible for the elevated TSA levels in acute myocardial infarction (AMI). Elevated serum SA levels might also be due to either shedding or secretion of free SA from the cell or cell membrane surface if neuraminidase levels are increased, or to the release of cellular SA-containing glycolipids and/or glycoproteins into plasma from myocardial cells after AMI. The aim of the present study was to investigate both the possible role of SA-rich inflammation-sensitive proteins and the cell damage due to elevated serum TSA levels in AMI. A possible role of serum LSA as an indicator of the shedding or secretion of SA from the cell or cell membrane surface in AMI was also evaluated. The study included 38 subjects with AMI and 32 healthy volunteers. Serum TSA and LSA were determined using the methods of Warren and Katopodis, respectively. The concentrations of serum SA-rich inflammation-sensitive proteins, namely α

scholarly journals Altered Na+/K+-ATPase expression plays a role in rumen epithelium adaptation in sheep fed hay ad libitum or a mixed hay/concentrate diet

2011 ◽  
Vol 56 (No. 1) ◽  
pp. 36-48 ◽  
Author(s):  
J. Kuzinski ◽  
R. Zitnan ◽  
T. Viergutz ◽  
J. Legath ◽  
M. Schweigel
Keyword(s):  
Cell Membrane ◽  
Mrna Expression ◽  
Surface Area ◽  
Morphological Changes ◽  
Membrane Surface ◽  
Membrane Surface Area ◽  
Cell Layers ◽  
Ad Libitum ◽  
Atpase Localization ◽  
Cell Membrane Surface

In this study we investigated rumen papillae morphology and the localization and expression of the<br />Na<sup>+/</sup>K<sup>+</sup>-ATPase&nbsp;in eight sheep fed hay ad libitum (h) or hay ad libitum plus additional concentrate (h/c). Four sheep were provided with the ad libitum h-diet for the complete three-week experimental period. The second group of four sheep received the h-diet for only one week and was fed the mixed hay/concentrate (h/c) diet for another two weeks. The amount of concentrate supplement was stepwise increased from 150 to 1000 g/day and given in two meals. Following slaughter rumen papillae from the atrium ruminis (AR), the rumen ventralis (RV) and the ventral blind sac (BSV) were fixed and examined for morphological changes and Na<sup>+</sup>/K<sup>+</sup>-ATPase localization by morphometric methods and immunohistochemistry. Ruminal epithelial cells (REC) originating from the strata basale to granulosum were also isolated. Cellular Na<sup>+</sup>/K<sup>+</sup>-ATPase expression (mRNA and protein) and differentiation state were determined by RT-PCR, Western blot, and flow cytometry. Compared with data from h-fed sheep, morphometric analysis revealed an increased length and width of rumen papillae in h/c-fed sheep, resulting in a marked 41% and 62% increase in rumen papillae surface in AR and RV, respectively. The rumen mucosa of h/c-fed sheep was characterized by a predominant stratum corneum (42 &plusmn; 0.7 &micro;m vs. 28 &plusmn; 0.5 &micro;m), but the thickness of the metabolically active cell layers remained unchanged. REC suspensions from sheep fed the h/c diet generally contained more cells (7.30 &plusmn; 0.83 vs. 3.49 &plusmn; 0.52 &times; 10<sup>7</sup>/ml; P &lt; 0.001) and an increased proportion of REC positive for basal cytokeratin and for the differentiation marker cytokeratin 10 (P &lt; 0.05). Cellular (cell membrane) and epithelial (stratum basale to stratum granulosum) Na<sup>+</sup>/K<sup>+</sup>-ATPase localization was similar between rumen regions and was not changed by concentrate feeding. After two weeks on the h/c-diet, a 96% increase in the absolute number of Na<sup>+</sup>/K<sup>+</sup>-ATPase-positive REC (6.56 &plusmn; 0.84 vs. 3.35 &plusmn; 0.51 &times; 10<sup>7</sup>/ml; P = 0.003) and a 61% elevation (P = 0.043) in Na<sup>+</sup>/K<sup>+</sup>-ATPase protein expression in REC from the upper third of the suprabasal cell layers were found. Moreover, a two-fold (P = 0.001) elevation in cell membrane surface area accompanied by a reduction (1.19 &times; 10<sup>&ndash;7</sup> &plusmn; 1.72 &times; 10<sup>&ndash;9</sup> arbitrary units (AU)/cm2 vs. 1.73 &times; 10<sup>&ndash;7</sup> &plusmn; 8.16 &times; 10<sup>&ndash;9</sup> AU/cm<sup>2</sup> in the h-group; P &lt; 0.001) in specific Na<sup>+</sup>/K<sup>+</sup>-ATPase fluorescence per cm<sup>2</sup> of cell membrane surface area was observed after h/c-feeding. Na<sup>+</sup>/K<sup>+</sup>-ATPase &alpha; subunit mRNA expression was also reduced (P &lt; 0.0001) from 0.154 &plusmn; 0.013 to 0.057 &plusmn; 0.004 pg per pg S18 mRNA control in the h/c-compared with the h-group. Thus, the h/c-diet led to a rapid increase in REC number and total cell membrane surface area in metabolically active and resorptive cell layers and was accompanied by a reduction in Na<sup>+</sup>/K<sup>+</sup>-ATPase mRNA expression and abundance per cell membrane surface area.

ВЛИЯНИЕ ХЛОРТЕТРАЦИКЛИНА НА ОБРАЗОВАНИЕ ПОР В ПЛАЗМАТИЧЕСКОЙ МЕМБРАНЕ КЛЕТОК ГРАНУЛЕЗЫ КОРОВ

2020 ◽  
Author(s):  
V.YU. DENISENKO
Keyword(s):  
Cell Membrane ◽  
Granulosa Cells ◽  
Fluorescent Probes ◽  
Membrane Surface ◽  
Inhibitory Effect ◽  
Cellular Viability ◽  
Cytoplasmic Calcium ◽  
Negative Effect ◽  
Cell Membrane Surface

Соединения, для которых отсутствуют необходимые рецепторы на поверхности клеток, не способны проникать внутрь клеток. Для обеспечения их поступления в клетки используются различные методы (пермеабилизация, инъекция этих соединений внутрь клетки и т. д.). Однако эти способы дорогостоящие в применении, либо оказывают на клетки эффект, не совместимый с дальнейшей жизнедеятельностью. Вход в нагруженные флуоресцентными зондами хлортетрациклин (ХТЦ) и Фура-2АМ клетки гранулезы коров различных соединений вызывает изменение концентрации цитоплазматического и запасенного во внутриклеточных депо кальция. В интактных нагруженных ХТЦ клетках гранулезы добавление пролактина (ПРЛ) стимулировало освобождение Са2 из внутриклеточных депо. В необработанных клетках гепарин не способен самостоятельно проникать в клетки. Для обеспечения входа гепарина в клетки используется процедура пермеабилизации, то есть клетки предварительно обрабатываются детергентом (дигитонином). Использование гепарина приводило к ингибированию освобождения Са2 из внутриклеточных депо, стимулированного добавлением ПРЛ. Обработка клеток детергентом дигитонином не оказывала влияния на стимулированное ПРЛ освобождение Са2 из депо и ингибирующее действие гепарина на выход Са2 из внутриклеточных депо. В интактных нагруженных Фура-2АМ клетках гранулезы добавление ПРЛ не приводило к увеличению концентрации цитоплазматического кальция.После обработки дигитонином нагруженных Фура-2АМ клеток гранулезы внесение ПРЛ приводило к увеличению концентрации цитоплазматического Са2, которое ингибировалось при добавлении гепарина. Полученные данные позволяют предположить, что ХТЦ образует поры на поверхности клеток гранулезы, способствуя таким образом проникновению в клетки различных соединений.Соединения, для которых отсутствуют необходимые рецепторы на поверхности клеток, не способны проникать внутрь клеток. Для обеспечения их поступления в клетки используются различные методы (пермеабилизация, инъекция этих соединений внутрь клетки и т. д.). Однако эти способы дорогостоящие в применении, либо оказывают на клетки эффект, не совместимый с дальнейшей жизнедеятельностью. Вход в нагруженные флуоресцентными зондами хлортетрациклин (ХТЦ) и Фура-2АМ клетки гранулезы коров различных соединений вызывает изменение концентрации цитоплазматического и запасенного во внутриклеточных депо кальция. В интактных нагруженных ХТЦ клетках гранулезы добавление пролактина (ПРЛ) стимулировало освобождение Са2 из внутриклеточных депо. В необработанных клетках гепарин не способен самостоятельно проникать в клетки. Для обеспечения входа гепарина в клетки используется процедура пермеабилизации, то есть клетки предварительно обрабатываются детергентом (дигитонином). Использование гепарина приводило к ингибированию освобождения Са2 из внутриклеточных депо, стимулированного добавлением ПРЛ. Обработка клеток детергентом дигитонином не оказывала влияния на стимулированное ПРЛ освобождение Са2 из депо и ингибирующее действие гепарина на выход Са2 из внутриклеточных депо. В интактных нагруженных Фура-2АМ клетках гранулезы добавление ПРЛ не приводило к увеличению концентрации цитоплазматического кальция.После обработки дигитонином нагруженных Фура-2АМ клеток гранулезы внесение ПРЛ приводило к увеличению концентрации цитоплазматического Са2, которое ингибировалось при добавлении гепарина. Полученные данные позволяют предположить, что ХТЦ образует поры на поверхности клеток гранулезы, способствуя таким образом проникновению в клетки различных соединений.In the absence of the necessary receptors on the cell membrane surface, the compounds are not able to penetrate into the cells. Various methods are used to ensure the entry of such compounds into the cells (permeabilization, compound injection into the cell, etc.), however, all these methods are expensive to use or have a negative effect on the cellular viability. The penetration of various compounds into the granulosa cells of cows treated with chlortetracycline (CTC) and Fura-2AM fluorescent probes causes a change in the concentration of cytoplasmic calcium and calcium stored in intracellular stores. In intact CTC-treated granulosa cells, the addition of prolactin (PRL) stimulated the Ca2 release from the intracellular stores. In untreated cells, heparin is not able to independently penetrate into the cells. To ensure the penetration of heparin into the cells, the permeabilization procedure when the cells are pre-treated with a detergent (digitonin). The usage of heparin led to the inhibition of Ca2 release from the intracellular stores stimulated by the PRL. The treatment of the cells with digitonin did not affect the PRL-stimulated release of Ca2 and the inhibitory effect of heparin on the Ca2 release from the stores. In intact Fura-2AM-treated granulosa cells, the addition of PRL did not increase the concentration of cytoplasmic calcium. After digitonin treatment of Fura-2AM-treated granulosa cells, the supplementation of PRL led to an increase in the concentration of cytoplasmic Ca2, which was inhibited by the heparin addition. The obtained data suggest that CTC forms pores in the membrane of granulosa cells facilitating the penetration of various compounds into cells.

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