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1

Analysis of mitochndrial membrane potential [delta psi] with fluorescent probes

100%

Cassarizza A., Salvioli S., Franceschi C.

Postępy Biologii Komórki

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1997

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tom 24

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nr 4

575-585

2

Application of ion-selective microelectrode in measurement of intracellular chloride activity in ciliate Blepharisma japonicum

88%

Fabczak S., Fabczak H.

Acta Protozoologica

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1989

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tom 28

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nr 3-4

3

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Does the membrane potential control incorporation of tubulovesicles into the secreting apical membrane of the rat parietal cell?

88%

Ostrowski J., Dolowy K., Zych W., Butruk E.

Journal of Physiology and Pharmacology

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1991

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tom 42

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nr 4

The present studies were designed to examine the effect of changes in membrane potential by means of protonophore carbonyl cyanide m-chlorophenylhydrazone (СССР) and variations in the pH of the medium on the secretory response of parietal cells. Studies were performed in vitro using isolated cells from rat stomachs and acid production was indirectly determined by ¹⁴C-aminopyrine (AP) accumulation. СССР affected both basal and histamine-stimulated AP accumulation in a concentration-dependent manner. The AP accumulation ratios depended on pH of the incubation medium; the ratio was lowest at pH 6.6, and increased progressively as the pH of the medium increased to 7.8. Moreover, the decreases in AP accumulation ratios caused by simultanous addition of СССР and AP to cell suspensions compared to those in which СССР was added to incubated cells after achieving the steady-state of AP accumulation were quantitatively similar. These findings suggest that the decrease in AP accumulation due to СССР treaiment is a consequence of an activation of acid secretion rather than an inhibitor of acid production. From the present and previously published data, we propose a working hypothesis: membrane recycling is dependent on changes in apical membrane potential.

4

Fluctuations of lipid-like membranes potential induced by glycine esters

88%

Podolak M., Kocherginsky N. M., Osak I. S., Przestalski S.

Biophysics of Membrane Transport

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1994

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tom 12

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nr 2

5

The pH-dependent effect of mitochondria on Ca2plus influx into Jurkat cells

88%

Zablocki K., Makowska A., Szczepanowska J., Duszynski J.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

6

The resting and action membrane potentials of ciliate Blepharisma japonicum

75%

Fabczak S., Fabczak H.

Acta Protozoologica

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1988

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tom 27

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nr 2

7

Free potassium and membrane potentials in cells of Blepharisma japonicum

75%

Fabczak S.

Acta Protozoologica

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1990

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tom 29

|

nr 3

75%

Trela Z., Radecki J., Przestalski S.

Polish Journal of Environmental Studies

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1997

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tom 06

|

nr 4

The effect of triphenyllead chloride on membrane potential and electrical conductance of internodal cells of the alga Nitellopsis obtusa was studied. It was found that the compound studied, when present at 50 μM concentration, caused membrane depolarization and increased electrical conductance. The effect is, however, observed only after 0-30 min incubation, which may be due to the cumulation of triphenyllead in the cell wall before direct contact with the plasma membrane could occur. After 30 min incubation in triphenyllead solution the average relative changes in the membrane potential and electric conductance were -0.1±0.04 and 0.33±0.08 (n=12), respectively. These changes may be due to increased permeability of chloride ionsbrought about by the compound's interaction with channel proteins, or increased unspecific leakage of ions induced by a disturbance in the membrane structure.

14

Expression of Helicobacter pylori ggt gene in baculovirus expression system and activity analysis of its products

63%

Kong M., Xu M., He Y.-L., Zhang Y.-L.

Polish Journal of Microbiology

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2011

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tom 60

|

nr 3

The γ-glutamyltranspeptidase (GGT) of Helicobacter pylori (HpGT) is a newly found virulence factor. In an approach to gain insight into the gene function, the four domains of the HpGT were cloned and expressed in baculovirus expression system. The results of a functional assay showed that the HpGT products acted as GGT, even when the N-terminal 380 amino acids were deleted. However, only the full length open reading frame (ORF) of the HpGT gene was apparently e$ective on cell growth. This result indicated that the products of the full length ORF might have an important role in gastric carcinogenesis. In this paper, we are the first to report that changes of mitochondrial membrane potential can be detected using 5, 5’, 6, 6’-tetrachloro-1, 1’, 3, 3’-tetraethylbenzimidazole carbocyanine iodide (JC-1) staining in insect cells.

15

Activation of the intrinsic and extrinsic pathways in high pressure-induced apoptosis of murine erythroleukemia cells

63%

Yamaguchi T., Hashiguchi K., Katsuki S., Iwamoto W., Tsuruhara S., Terada S.

Cellular and Molecular Biology Letters

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2008

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tom 13

|

nr 1

49-57

We previously demonstrated that caspase-3, an executioner of apoptosis, is activated in the pressure-induced apoptosis of murine erythroleukemia (MEL) cells (at 100 MPa). Here, we examined the pathway of caspase-3 activation using peptide substrates and caspase inhibitors. Using the substrates of caspases-8 and -9, it was found that both are activated in cells under high pressure. The production of nuclei with sub-G1 DNA content in 100 MPa-treated MEL cells was suppressed by inhibitors of caspases-8 and -9, and pan-caspase. In 100 MPa-treated cells, pan-caspase inhibitor partially prevented the cytochrome c release from the mitochondria and the breakdown of mitochondrial membrane potential. These results suggest that the intrinsic and extrinsic pathways are activated in apoptotic signaling during the high pressure-induced death of MEL cells.

16

Evidence for state-dependent block of DPI 201-106, a synthetic inhibitor of Na+ channel inactivation, on delayed-rectifier K+ current in pituitary tumor (GH3) cells

63%

Wang Y.-J., Lin M.-W., Lin A.-A., Peng H., Wu S.-N.

Journal of Physiology and Pharmacology

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2008

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tom 59

|

nr 3

409-423

DPI 201-107 (DPI), a diphenylpiperazinylindole derivative, was reported to be a cardio-selective modifier of voltage-gated Na+ channels. It remains unclear whether DPI has any effects on ion currents. The effects of DPI on ion currents and membrane potential in pituitary tumor (GH3) cells were investigated in this study. DPI (1-100 µM) suppressed the amplitude of delayed-rectifier K+ current (IK(DR)) in a concentration-dependent manner with an IC50 value of 9.4 µM. The presence of DPI also enhanced the rate and extent of IK(DR) inactivation. Recovery from block by DPI (10 µM) was fitted by a single exponential. Crossover of tail currents during the exposure to DPI was also observed. Under current-clamp recordings, DPI prolonged action potential duration in GH3 cells. With a minimal binding scheme, DPI-induced block of IK(DR) was quantitatively provided. The exposure to DPI also blocked IK(DR) with a concomitant increase in current inactivation in NG108-15 neuronal cells. Taken together, the results imply that DPI acts as an open-channel blocker of delayed-rectifier K+ channels in these cells. The widening of action potentials induced by DPI in these cells may be explained mainly by its block of IK(DR) in a state-dependent manner.

17

Stimulation of large-conductance Ca2plus-activated Kplus channels by the Naplus-Ca2plus exchanger inhibitor dichlorobenzamil in cultured human umbilical vein endothelial cells and mouse aortic smooth muscle cells

63%

Liang G. H., Park S., Kim J. A., Choi S., Suh S. H.

Journal of Physiology and Pharmacology

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2009

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tom 60

|

nr 1

43-50

We investigated the effects of the selective inhibitor of Na+/Ca2+ exchanger (NCX), 2',4'- and 3',4'-dichlorobenzamil (DCB), on large-conductance Ca2+-activated K+ (BKCa) channels in cultured human umbilical vein endothelial cells (HUVECs) and fresh isolated mouse aortic smooth muscle cells (MASMCs) using the patch clamp techniques. Both kinds of DCB reversibly activated BKCa currents in whole-cell clamped HUVECs or MASMCs. The EC50 of 2',4'-DCB for BKCa current activation in HUVECs was 2.64 ± 0.10 µM. In inside-out and outside-out patches, 2',4'-DCB remarkably increased BKCa channels activity. 2',4'-DCB increased open frequency, but had no significant effect on mean open time. In inside-out patches, 2',4'-DCB shifted the relationship curve between [Ca2+]i and open probability (NPo) to the left; the [Ca2+]i required to evoke half-maximal activation changed from 1087.45 ± 142.91 nM to 500.24 ± 66.83 nM by 10 µM 2',4'-DCB. In addition, 2',4'-DCB shifted the relationship curve between membrane potential and NPo to the left; the membrane potential to evoke half-maximal activation changed from 81.1 ± 2.4 to 64.7 ± 3.1 mV by 10 µM 2',4'-DCB. 3',4'-DCB also increased BKCa channels activity. There was no significant difference in the effect of DCB on BKCa channels between both excised patches. These results suggested that 2',4'- and 3',4'-DCB activate BKCa channels activity in HUVECs and MASMCs by increasing the sensitivity of BKCa channels to cytosolic free Ca2+ and membrane potential. Our report would provide a consideration if they are used as NCX blocker in vascular endothelial cells or smooth muscle cells.

18

Differentiated Paju cells have increased resistance to toxic effects of potassium ionophores

63%

Teplova V., Jaaskelainen E., Salkinoja-Salonen M., Saris N. E. L., Serlachius M., Li F. Y., Andersson L. C.

Acta Biochimica Polonica

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2004

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tom 51

|

nr 2

In this study we have investigated the impact of differentiation of neuronal cells on their sensitivity to microbial toxins. We used the human neural crest-derived tumor cell line Paju, which can be induced to differentiation in vitro by treatment with phorbol 12-myristate 13-acetate. Addition of the highly toxic potassium ionophores cereulide (4.5 and 9.0 ng/ml) or valinomycin (20 ng/ml), to cultures of undifferentiated Paju cells caused collapse of the mitochondrial membrane potential — measured with the fluorescent probe 5,5',6,6'-tetrachloro-1,1',3,3'-tetrabenzimidazole carbo- cyanine iodide (JC-1) followed by detachment of the cells and their apoptotic death. After induced differentiation of the Paju cells, their mitochondria retained the membrane potential upon exposure to the toxins and the cells displayed increased resistance to apoptosis as compared with undifferentiated cells. This effect may be caused by an elevated expression of the anti-apoptotic protein Bcl-2 and of the neuroprotective factor, stanniocalcin, in differentiated cells.

19

The effect of low power laser radiation on the Chinese hamster fibroblast cell membrane potential

63%

Rekawiecka K., Palecz D., Schussler H., Bryszewska M.

Cellular and Molecular Biology Letters

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1997

|

tom 02

|

nr 2

The membrane potential of Chinese hamster fibroblasts was determined to be (-29,9 ± 6.5) mV. Fibroblast membranes irradiated with red laser light of 670 nm were partially depolarized. This effect was observed for energy doses of 5 J and 10 J. The energy dose of 15 J did not further decrease the membrane potential. In contrast to the red light, the irradiation with green laser light (543.5 nm) did not change fibroblast membrane potential.

20

Effects of apigenin on membrane potential in the liverwort Conocephalum conicum

63%

Pawlikowska-Pawlega B., Krol E., Trebacz K., Gawron A.

Biological Letters

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2005

|

tom 42

|

nr 2 Spec.Vol.

Ograniczanie wyników

Analysis of mitochndrial membrane potential [delta psi] with fluorescent probes

Application of ion-selective microelectrode in measurement of intracellular chloride activity in ciliate Blepharisma japonicum

Does the membrane potential control incorporation of tubulovesicles into the secreting apical membrane of the rat parietal cell?

Fluctuations of lipid-like membranes potential induced by glycine esters

The pH-dependent effect of mitochondria on Ca2plus influx into Jurkat cells

The resting and action membrane potentials of ciliate Blepharisma japonicum

Free potassium and membrane potentials in cells of Blepharisma japonicum

Effects of visible light and fusicoccin on membrane potential and pH of the incubation medium of Sagittaria leave cells

Determination of cytosolic sodium in Stentor cells with monensin-based Na plus - selective microelectrode

The effects of tetraethylammonium on the excitability of marine ciliate Fabrea salina

Contributions of fast and slow potassium outward currents to repolarization of the action potential in Euplotes vannus

Effects of quercetin and verapamil on membrane potential in the liverwort Conocephalum conicum

Effect of triphenyllead chloride on the resting potential and electrical conductance of Nitellopsis obtusa membrane

Expression of Helicobacter pylori ggt gene in baculovirus expression system and activity analysis of its products

Activation of the intrinsic and extrinsic pathways in high pressure-induced apoptosis of murine erythroleukemia cells

Evidence for state-dependent block of DPI 201-106, a synthetic inhibitor of Na+ channel inactivation, on delayed-rectifier K+ current in pituitary tumor (GH3) cells

Stimulation of large-conductance Ca2plus-activated Kplus channels by the Naplus-Ca2plus exchanger inhibitor dichlorobenzamil in cultured human umbilical vein endothelial cells and mouse aortic smooth muscle cells