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At least 775 records · Page 43Linked to original sources
PubMed1996

Effects of beta-adrenoceptor antagonists on Ca(2+)-overload induced by lysophosphatidylcholine in rat isolated cardiomyocytes.

1. The effects of beta-adrenoceptor antagonists including (-)- and (+)-propranolol, (-)- and (+)-penbutolol, timolol, pindolol, atenolol, acebutolol and practolol on the Ca(2+)-overload induced by lysophosphatidylcholine (LPC) were examined in isolated cardiomyocytes of the rat. 2. Fura-2 was used for measurement of the intracellular calcium concentration ([Ca2+]i). LPC (15 microM) produced a rapid increase in [Ca2+]i from 72 +/- 5 to 3042 +/- 431 nM which coincided with a decrease in the percentage of rod-shaped cells from 69 +/- 2 to 5 +/- 2%. 3. Preincubation with (-)-propranolol (20 microM), (+)-propranolol (50 microM), or (-)- or (+)-penbutolol (20 microM), the lipophilicity of which is higher than other beta-adrenoceptor antagonists, significantly inhibited both the increase in [Ca2+]i and the cell-shape change induced by 15 microM LPC. The inhibitory effects of the four drugs on the LPC-induced increase in [Ca2+]i and cell-shape change were concentration-dependent. The IC50S of (-)-propranolol, (+)-propranolol, (-)- and (+)-penbutolol for the increase in [Ca2+]i were 1.28, 10.50, 0.67 and 0.76 microM, respectively. 4. Pretreatment with pindolol, timolol, acebutolol, practolol, atenolol or lignocaine did not inhibit the increase in [Ca2+]i and the morphological change induced by LPC. 5. LPC markedly increased the release of creatine phosphokinase from 9 +/- 1 to 45 +/- 2% which could be significantly reduced by (-)- or (+)-propranolol but not by acebutolol or timolol. 6. The protective effects of (-)- and (+)-propranolol, (-)- and (+)-penbutolol against the Ca(2+)-overload induced by LPC were not associated with the beta-adrenoceptor antagonistic action, but probably with an unknown action which is related to the preservation of membrane integrity. Further studies are necessary to clarify the exact mechanisms of the protective action of these beta-adrenoceptor antagonists against the Ca(2+)-overload induced by LPC.

Adrenergic beta-Antagonists↗
PubMed2007

In vitro comparison of chlorhexidine and povidone-iodine on the long-term proliferation and functional activity of human alveolar bone cells.

This work reports the behaviour of osteoblastic human alveolar bone cells (first subculture) in the presence of chlorhexidine (CHX) and povidone-iodine (PI). Short contact (2 min) of 24-h cultures with CHX, at 0.12 and 0.2%, and PI, at 5 and 10%, caused cell death within minutes; contact with 1% PI resulted in loss of the elongated characteristic cell shape. Cell adhesion was adversely affected at concentrations higher than 5 x 10(-5)% CHX or 0.05% PI. Long-term exposure to CHX at 10(-5) and 10(-4)% or PI at 10(-4)% had little effect on cell growth and caused an induction in the synthesis of alkaline phosphatase (ALP). Concentrations of CHX and PI similar and higher than, respectively, 5 x 10(-4)% or 0.05% caused dose-dependent deleterious effects. CHX affected mainly the cell growth, whereas the effects of PI were observed mostly in ALP production and matrix mineralization. Considering the levels of CHX and PI used routinely in the oral cavity, results suggest that CHX has a higher cytotoxicity profile than PI. This observation might have some clinical relevance regarding the potential utility of PI in the prevention of alveolar osteitis.

Adult↗
PubMed2001

MRNA expression on shape-engineered endothelial cells: adhesion molecules ICAM-1 and VCAM-1.

This study was designed to assess the effect of cell shape on mRNA expression of two adhesion molecules, intracellular adhesion molecule-1 and vascular adhesion molecule-1, on endothelial cells. Photo-microprocessing using photoreactive poly(ethylene glycol) produced two different patterned-cell adhesive regions on tissue culture dishes: one is a striped region on which adhered cells are highly elongated and aligned along the long axis of the striped pattern, and the other is a circular region on which cells are less spread out and rounded. mRNA expressions, measured by the reverse transcription-polymerase chain reaction technique, revealed higher mRNA expression for intracellular adhesion molecule-1 and lower mRNA expression for vascular adhesion molecule-1 on elongated cells than those on round cells. This indicates that surface-induced cell shape induces changes in the mRNA expression of these molecules. The significance of cell-shape-induced mRNA expression is discussed in conjunction with the experimental results of flow-induced expression at molecular and mRNA levels.

Cell Adhesion↗
PubMed2007

Shape-engineered fibroblasts: cell elasticity and actin cytoskeletal features characterized by fluorescence and atomic force microscopy.

The regulation of cell shape, which determines cell behaviors including adhesion, spreading, migration, and proliferation in an engineered artificial extracellular milieu, is an important task in tissue engineering and in development of functional biomaterials. To deepen the understandings of shape-dependent cell mechanics, the cell elasticity and structural features of the actin cytoskeleton (CSK) were characterized for shape-engineered fibroblasts; round and spindle-shaped cells cultured on photolithographically microprocessed surfaces, employing the cellular microindentation tests and fluorescence observation of actin CSK by the combination of atomic force microscopy (AFM) and fluorescence microscopy (FM). The relationships among cell elasticity, the structural features of actin CSK, and engineered cell shape were analyzed and compared with those of control cells that had been cultured on nonprocessed surfaces (termed naturally extended cells). Results showed that the spindle-shaped cells with sparse or no apical stress fibers (ASFs) exhibited similar stiffness to that of the naturally extended cells with dense ASFs. The elasticity of spindle-shaped cells was affected only slightly by the stress fiber (SF) density, which is in marked contrast to the significant correlation shown between cell elasticity and SF density in naturally extended cells. This result implies that the elasticity of regionally restricted adhesion-surface-induced shape-engineered cells, particularly of highly elongated cells, is affected predominantly by cell shape rather than by structural features of SFs.

3T3 Cells↗
PubMed2006

Differential responses of pulmonary endothelial phenotypes to cyclical stretch.

Endothelial phenotypes derived from different pulmonary vascular segments have markedly different permeability response to inflammatory agonists, but their responses to mechanical strain have not been characterized. Therefore, we evaluated the effect of cyclical stretch on cell shape, cell membrane wounding, and junctional beta-catenin in rat pulmonary artery (RPAEC) and microvascular (RPMVEC) endothelial cell monolayers. After 24 h of 24% uniaxial strain at 40 cycles/min, RPAEC but not RPMVEC reoriented transverse to the axis of strain. Total beta-catenin increased in RPAEC but decreased in RPMVEC. Transient plasma membrane wounding was produced by cyclical biaxial strain of 34% or by scratching of monolayers with a needle and was indicated by retention of lysine fixable fluorescent 70 kDa dextran. Junctional beta-catenin was quantified by fluorescence intensity and image analysis. beta-catenin fluorescence was significantly lower in wounded cells than in adjacent uninjured cells in both phenotypes, and the decrease was significantly greater in RPAEC compared to RPMVEC in both scratched (57% vs. 30%) and stretched (55% vs. 37%) cells. Using immunoprecipitation, VE-cadherin-associated beta-catenin decreased significantly in RPAEC (61%) but E-cadherin-associated beta-catenin was not significantly decreased in RPMVEC after 34% biaxial cyclical strain. These data suggest that RPAEC more readily remodel cell-cell adhesions during cyclical stretch than RPMVEC and that a reduced intercellular adhesion adjacent to wounded cells could serve as transvascular leak sites in both phenotypes.

Adaptation, Physiological↗
PubMed1993

Flask cells and flask-shaped glandular cells of amphibian skin specifically produce fucose-rich glycoproteins.

A battery of horseradish peroxidase-conjugated lectins has been employed as a cytochemical tool for the labelling of specific cell types in amphibian epidermis. Among the lectins used, only Ulex europaeus I (UEA I) showed specific reaction with the cytoplasm of flask cells. In addition, UEA I stained flask-shaped secretory cells in dermal glands and a reaction on glandular ductal cells was also observed. At the electron microscopic level, lectin binding was found in granules distributed among mitochondria in the cytoplasm of flask cells and in larger mucous granules of flask-shaped glandular cells, which were released into the lumen. UEA I also stained the extracellular space above flask cells. The labelling was due mainly to a glycoprotein of mol. wt. approx. 27 kDa. Structural and cytochemical similarities between flask cells and flask-shaped cells of dermal glands could be a consequence of a common secretory role of both cell types.

Animals↗
PubMed1985

[Role of microtubules and intermediate filaments in maintaining the shape of epithelial cells].

The role of microtubules and intermediate filaments in control of cell shape of cultured cells of hepatomas McA-RH-7777 and 27 was investigated. Indirect immunofluorescence with specific polyclonal antibodies against tubulin and monoclonal antibodies against prekeratin with molecular weight 49 kD and vimentin was used. Incubation of cells in colcemid, resulting in specific distribution of microtubules did not change either prekeratin or vimentin distribution in cells of both the hepatomas, but reversed polarization of elongated McA-RH-7777 cells. These data suggest that the effect of disruption of microtubular system on the cell shape is not mediated by alterations of intermediate filaments.

Animals↗
PubMed2003

Neural activity in prefrontal cortex during copying geometrical shapes. I. Single cells encode shape, sequence, and metric parameters.

In drawing a copy of a geometrical shape, a sequence of movements must be produced to represent the sides of the object in the proper spatial relationship. We investigated neural mechanisms of this process by training monkeys to draw (using a joystick) copies of geometrical shapes (triangles, squares, trapezoids and inverted triangles) presented on a video monitor while recording single cell activity in prefrontal cortex. The drawing trajectories monkeys produced were divided into a series of discrete segments, varying in direction and length. We performed a stepwise multiple linear regression analysis to identify those copy parameters significantly influencing cell activity. The copied shape (e.g., triangle, square) and the serial position of the segment within each trajectory were the most prevalent effects (in 46% and 43% of cells, respectively), followed by segment direction (32%) and length (16%). Effects of temporal factors (maximum segment speed and time to maximum segment speed) were less frequent. These results demonstrate that prefrontal neurons encode several spatial and sequence variables that define copy trajectories. We also found that specific groupings of significant effects tended to occur together in single neurons. Specifically, single neurons simultaneously processed the serial position of a segment within each trajectory along with the corresponding spatial (but not temporal) attributes of that segment (i.e., direction and length), as well as with the overall shape to which the segments belong. Finally, we discovered that relationships between neural activity and segment serial position were systematic in many instances, described by monotonically increasing and decreasing functions, as well as parabolic functions. These findings indicate that, within the copying task, the serial segment position is a key factor for neural activity in the periprincipalis area of the prefrontal cortex.

Action Potentials↗
PubMed1994

Partially oxygenated sickled cells: sickle-shaped red cells found in circulating blood of patients with sickle cell disease.

A previously uncharacterized type of sickled cell was found in venous blood of patients with sickle cell disease when blood was collected without exposure to air and fixed immediately with 1% glutaraldehyde solution equilibrated with 5% oxygen. These cells were either elongated, resembling irreversibly sickled cells (ISCs), or nonelongated, with a raisin-like shape. Both types assumed a normal discoidal shape upon full oxygenation. Since these cells exist only under partially oxygenated conditions, they are described as partially oxygenated sickled cells (POSCs). POSCs are morphologically distinct from partially deoxygenated sickled cells formed during deoxygenation by having rounded edges, while the latter have sharp edges. Transmission electron microscopy of POSCs revealed various amounts of misaligned Hb S polymers. Investigations in vitro demonstrated the formation of POSC-like cells by partial oxygenation of deoxygenated cells. Since POSCs contain intracellular fibers and sickle readily upon deoxygenation, they may have clinical and pathological significance.

Anemia, Sickle Cell↗
PubMed1990

Cyclic AMP-induced shape changes of astrocytes are accompanied by rapid depolymerization of actin.

Agents that increase intracellular cyclic AMP produce a process-bearing morphology in astrocytes. We have examined short-term re-arrangements of the astrocyte cytoskeleton during this shape conversion. Primary cultures of astrocytes from neonatal rat forebrain were grown at low density as polygonal shaped cells. Treatment with 1 mM dibutyryl cAMP in the absence of serum produced rapid changes in cell shape (100% of cells as flat to 90% showing cytoplasmic contraction and processes in 60 min). In the presence of serum, similar changes took place, but more slowly. No changes in total cellular levels of GFAP, vimentin, tubulin or actin were observed over a 2-h period of treatment. There was a shift in actin from a Triton X-100-insoluble pool to a soluble pool, with a 40% reduction in insoluble actin. The kinetics of this shift paralleled kinetics of shape change. The shift also corresponded to a loss of stress fibers, visualized with rhodamine-phalloidin. Intermediate stages of stress fiber loss were observed as short, wavy or small ring profiles. Colchicine prevented the dBcAMP-induced changes in shape. If cells were first treated with taxol, however, subsequent exposure to colchicine did not inhibit contraction. Thus, dBcAMP, presumably through a cAMP-dependent kinase, depolymerizes actin in stress fiber form as cells contract. In addition, an intact microtubule system may be required for the changes in shape. Treatment with dBcAMP also caused the disappearance of vinculin-containing attachment sites, indicating that adhesion plaques, or at least the association of vinculin with them, are lost during the time of microfilament bundle dissociation.

Actins↗
PubMed1997

Cobra venom cardiotoxin induces perturbations of cytosolic calcium homeostasis and hypercontracture in adult rat ventricular myocytes.

The effects of Cobra venom cardiotoxin (CTX) on the cellular morphology, twitch amplitude and intracellular calcium ([Ca2+]i) of the ventricular myocytes were studied. [Ca2+]i and twitch amplitude were determined with a fluorometric ratio method using Fura-2/AM and Calcium Green-1 as calcium indicators, and a videomicroscopic technique, respectively. Addition of 0.001-1 microM CTX led to a time-dependent loss of rod shaped cells, beginning at 1 min, and remaining stable by 20 min. CTX 1 microM initially caused a transient augmentation in amplitude of the electrically induced-[Ca2+]i transient and twitch amplitude in the single cardiac myocyte. This was followed by a prolongation in duration of [Ca2+]i. Eventually, cells became inexcitable and abruptly underwent contracture, and [Ca2+]i remained elevated. In the absence of electrical stimulation, 1 microM CTX induced a Ca2+ spike followed by a sustained elevation of [Ca2+]i, an effect different from that of 40 mm KCl or 10 mm caffeine, which caused a transient elevation in [Ca2+]i. Digital imaging microscopy of Calcium Green-1 fluorescence revealed that the increase in [Ca2+]i was accompanied by changes in cell shape without leakage of fluorescence dye in the early stage after administration of the toxin. In the absence of [Ca2+]o, the initial [Ca2+]i spike was reduced, but the second phase of elevation of [Ca2+]i still occurred. In addition, experiments using Mn2+ quench technique suggested that Ca2+-influx was induced by CTX, and that both ryanodine and thapsigargin, known to deplete Ca2+ from its intracellular pool, abolished the second phase of the elevation of [Ca2+]i. The effects of cardiotoxin were abolished by 10 mM Ni2+ and 10 mM -Ca2+-o, but not by 5 microM verapamil. In conclusion, the observations indicate that CTX causes an initial increase followed by a second sustained elevation in [Ca2+]i, which is accompanied by changes in cell shape-from rod to round-and hypercontracture. The initial [Ca2+]i spikes were attributed to the extracellular Ca2+ influx, while the second [Ca2+]i elevation was related to internal Ca2+ release. The high [Ca2+]i may be responsible for hypercontracture and cell death. Further studies are needed to verify it.

Animals↗
PubMed1986

Anchorage and lymphocyte function: collagen and the maintenance of motile shape in T cells.

When cultured on a collagen matrix at a density of 7 X 10(4) cells/cm2 for 48 hr, 80 +/- 10% of unfractionated and 70 +/- 14% of T-enriched human blood lymphocytes from eight healthy individuals developed a motile morphology defined as the presence of lamellar surface activity and cytoplasmic flattening. During culture on plastic for 48 hr, 32 +/- 5% of unfractionated and 38 +/- 6% of T-enriched lymphocytes from the same individuals developed a motile morphology. The motile morphology was not a rigid state but a series of oscillations in cell shape. The conversion from a spherical into a motile morphology was independent of cell density. After preculture on plastic at 'high' density (1.5 X 10(6) cells/cm2), and subsequent transfer to a plastic surface, 54 +/- 12% of the cells from separate individuals exhibited a motile morphology within 2 hr. These motile forms were, however, transient and approximately 50% disappeared within 12 hr. Collagen augmented the motile behaviour of unfractionated and T-enriched lymphocytes by two to four times when fresh from the blood compared with glass or plastic. During culture on plastic, the lymphocytes lost this prompt responsiveness to collagen contact. Thus, during culture on plastic, the ratio between percentage motile lymphocytes after subsequent transfer to collagen and plastic, respectively decreased from values between 2 and 4 immediately after purification to close to 1 within 2 days. However, when retransferred to collagen, the majority of the lymphocytes within another 2-day period acquired responsiveness to collagen measured as potentiation of motile cell shape on this substrate compared with on plastic. These data suggest that the variation in motile behaviour in the T lymphocyte reflects a labile property which is enhanced by contact with a collagen matrix.

Adult↗
PubMed1987

Effects of colchicine on the shape of chick neuroepithelial cells during neurulation.

We have analyzed the effects of colchicine on the cell shapes in chick neuroepithelium. Cell shapes were ascertained by the position of the nucleus in plastic serial sections. We tested three colchicine doses (5 X 10(-5) M, 5 X 10(-6) M, and 5 X 10(-7) M) by two experimental treatments (in ovo and in vitro). Colchicine treatment in vitro is always effective in depolymerizing microtubules of neuroepithelial cells and reduces the percentages of wedge-shaped cells in the median area of neuroepithelium. The same effect can be observed when the embryos are treated with 5 X 10(-5) M or 5 X 10(-6) M colchicine in ovo. A concentration of colchicine of 5 X 10(-7) M in ovo cannot disrupt microtubules in stage 8 and stage 10 embryos, and the percentage of wedge-shaped cells is the same as that of the untreated cells. In stage 6 embryos this colchicine dose effects the microtubules and the percentages of wedge-shaped cells. These facts are interpreted in respect to variations in microtubular resistance to microtubular-disrupting agents that are shown by the neuroepithelial cells from different developmental stages.

Animals↗
PubMed1991

Cell-substratum interactions and the cytoskeleton in cell shape-mediated growth regulation of lens epithelial cells.

Cell attachment to a suitable substratum is a precondition for the mitotic growth of nontransformed lens epithelial cells. Cultering of cells in suspension results in a strong decline of the DNA synthetic rate, whereas reattachment induces the reentrance into the cell cycle. Further studies revealed that not anchorage itself but cell flattening is prerequisite for the entrance of cells into the cycle. Flattened cells exert tension to the substratum via numerous filopodia. If the rigidity of the substratum is reduced by loosening of the collagen gel from the bottom of the petri dish, the gel becomes contracted by the traction forces of the cells and the cell shape becomes transformed from a flattened shape into a more spheroidal or longstretched one. This cell shape transition is connected with a decrease in RNA- and protein synthesis and a stop of DNA synthesis. During further experiments it was demonstrated that microfilaments are involved in gel contraction and cell shape alteration, respectively. Furthermore, intact microfilaments are needed for G0-G1-S-transition. Desintegration of microfilaments by cytochalasin is without influence on ongoing DNA synthesis but hinders strongly the entrance of cells into the S-phase. The survey gives some recent results on the molecular basis of cell substratum interactions as well as the structure and function of the cytoskeleton. The role of the cytoskeleton in cell shape-mediated growth regulation is discussed.

Cell Adhesion↗
PubMed1998

Mechanical interactions among cytoskeletal filaments.

Mechanical properties of the cells are important in controlling cell shape, cell migration, and other functions. To understand how cytoskeletal (CSK) filaments interact with one another mechanically, mechanical properties of adherent endothelial cells were analyzed after treatment with CSK-disrupting drugs. CSK stiffness (the ratio of applied stress to strain, a measure of cell resistance to shape deformation), viscosity (an index of intracellular structural damping), and permanent deformation (a measure of "plasticity") were measured with magnetic twisting cytometry, by which rotational stress was applied directly to integrin receptors with ferromagnetic beads coated with RGD-containing peptide. Treatment with cytochalasin D, which disrupts actin microfilaments inhibited stiffness by 50% and decreased permanent deformation from 70% to 50% but had almost no effect on viscosity. In contrast, nocodazole, a microtubule disrupter, had very little effect on inhibition of CSK stiffness, decreased viscosity by 25%, and had no effects on permanent deformation. Acrylamide, an intermediate filament disrupter, had little effect on inhibition of CSK stiffness, little effect on viscosity, and no effect on permanent deformation. Taxol, a drug that facilitates microtubule polymerization, increased stiffness by 10%, increased viscosity by 10%, and decreased permanent deformation from 70% to 50%. Combinations of cytochalasin D and nocodazole, cytochalasin D and acrylamide, or all three drugs resulted in a synergistic effect on inhibition of CSK stiffness and viscosity but not in permanent deformation. Inhibition of oxidative metabolism with potassium cyanide had no effects on stress-induced stiffening response. Inhibition of tyrosine phosphatase with phenylarsine oxide had no effect on stress-induced stiffening response. We conclude that higher order mechanical interactions of CSK filaments are important in determining the mechanical properties of the cell.

Acrylamide↗
PubMed2007

Shape-engineered vascular endothelial cells: nitric oxide production, cell elasticity, and actin cytoskeletal features.

Single cell shape determines cellular functions. Therefore, control of cell shape is of considerable importance for the tissue engineering field. This study was designed to assess the effect of surface-induced shaping of vascular endothelial cells (ECs) on the intracellular nitric oxide (NO) production level, the cell elasticity, and cytoskeletal (CSK) features on shape-engineered ECs (round, 90, 120 microm diameter; spindle-shaped, 20, 30, 40 microm width) prepared on a photolithographically microprocessed surface. Intracellular NO production was measured using a microscopic spectrometer with diaminofluorescein diacetate probe. Cell elasticity and actin CSK features were analyzed through microindentation measurement and fluorescence observations with fluorescence and atomic force microscopy. Results showed that spindle-shaped cells exhibited lower NO production, higher cell stiffness, and denser actin stress fibers than the round and nonrestrictedly cultured control cells. Relations between cell shape with NO production, cell elasticity, and actin CSK features were discussed.

Actins↗
PubMed1976

Cyclic nucleotides, thioldisulfide status of proteins, and cellular control processes.

It is shown that cyclic nucleotides can have a variety of effects on cell division, cell shape, cell adhesion, and cell movement, depending on the cells selected and the conditions under which they are used. For example, while CHO cells elongate under the influence of exogenous dibutyryl CAMP, Y-1 adrenal tumor cells round up and polyoma-transformed 3T3 cells show no change in shape. The totality of experience with cyclic nucleotides suggests that where they have been used by cells as control elements involving the four processes listed above, they are superimposed on basic cellular processes that progress in their absence--that is, they must be acting indirectly. In attempting to understand the inhibitory action of methyl xanthines on egg development, we were forced to abandon the idea that they acted through cyclic nucleotides. We found that methyl xanthines inhibited the activation of glutathione reductase and that glutathione oxidizing agents act as mitotic inhibitors. Further, we found that tubulin polymerizability, NAD-kinase activity, and a mitotic apparatus associated Ca+2-ATP-ase were all inhibited by oxidation of some of their sulfhydryls and were activated by reduction of the resulting disulfides. These results are discussed in terms of reported cycles and activations of glutathione reductase (GR) in cells and reports that mixed disulfides of glutathione and proteins can act as substrates for GR. Using the fact that a CAMP-dependent protein kinase has been reported to be activated by glutathione, we have suggested potential sites where sulfhydryl control processes and cyclic nucleotide control processes and cyclic nucleotide control processes may interact in certain restricted cases.

Adenosine Triphosphatases↗
PubMed1984

Response of C3H/10T1/2 fibroblasts to an external steady electric field stimulation. Reorientation, shape change, ConA receptor and intramembranous particle distribution and cytoskeleton reorganization.

C3H/10T1/2 mouse embryo fibroblasts were stimulated by a steady electric field ranging up to 15 V/cm. The percentage of spindle-shaped cells increased with the field strength and duration of the stimulation. These cells oriented preferentially with their long axis perpendicular to the field direction. A small percentage of the cells were found to move slightly toward the cathode during the course of electric stimulation. Although no apparent field-induced redistribution of fluorescent-labelled concanavalin A (conA) receptor along the cell periphery was observed, the bright perinuclear area appeared preferentially on the anode side. Correlative fluorescence and scanning electron microscopy (SEM) revealed no difference in the density of conA-gold microsphere labels on either side of the cell. The density of intramembranous particles on the E-face of the plasma membrane was 54% higher on the anode side than on the cathode side of the cell. The microfilament bundles were observed to be disrupted after 30 min of 10 V/cm stimulation by rhodamine phalloidin labelling of F-actin. The cell sensitivity to electric field-induced reorientation and cell shape changes was reduced by pretreatment with conA, and to a lesser extent, with succinyl conA or wheat germ agglutinin (WGA). ConA pretreatment alone also reduced the prominence of microfilament bundles. However, post-field lectin binding to the cell has no effect on cell recovery. It is possible that the generally flat 10T1/2 cells retract and realign in order to minimize the disruption of their membrane potential. The conA binding-mediated receptor-cytoskeletal linkage temporarily immobilizes the cell and inhibits subsequent field-induced shape changes.

Actins↗