We have recently found that L-glutamate suppresses morphological changes of astrocytes induced by amyloid beta protein, adenosine 3',5'-cyclic monophosphate or phorbol ester in culture. To test the possibility that L-glutamate affects organization of the cytoskeleton, we investigated its effect on morphological changes induced by disruption of actin filaments with cytochalasin B. Cultured rat c...

Morphological changes are thought to contribute to the expression of long-term synaptic plasticity, a cellular basis for learning and memory. The mechanisms mediating the initiation and maintenance of the morphological changes are poorly understood. We repeatedly imaged the axonal arbors of mechanosensory neurons of Aplysia as they formed new synaptic varicosities and axonal branches after appl...

Various concentrations of actin (0.3 or 1 mM MgCl2, 1 mM ATP, 1 mM EGTA) reached their final degree of polymerization (measured by a pyrene dye attached to actin) earlier in the presence of cytochalasin B than in its absence. The curves relating concentrations of polymeric F-actin to total actin concentration were under these conditions highly nonlinear making an unambiguous extrapolation to ze...

The hypothesis that dynamic actin filaments participate in specific aspects of synaptic plasticity was investigated at the Schaffer-collateral-CA1 pyramidal cell synapse of mouse hippocampus. Low concentrations (0.01-1 microM) of compounds that inhibit actin filament assembly were bath applied to hippocampal slices during extracellular recording of field excitatory postsynaptic potentials. Cyto...

Mixtures of epithelial and stromal cells isolated from normal adult rabbit cornea, when cocultured in the presence of cytochalasin B, produced latent collagenase, whereas neither cell type alone, nor the mixture in the absence of this agent, did so. The enzyme, a characteristic animal collagenase, required proteolytic activation. The relative concentrations of epithelial and stromal cells had a...

PURPOSE To determine the effect of cytochalasin D on outflow facility in the human anterior segment, and the histologic changes that accompany the effect. METHODS Human anterior segments were studied in perfusion organ culture. The anterior segment from one eye received cytochalasin D, and that from the fellow control eye received vehicle; doses ranged from 0.06 mg/ml to 27.7 mg/ml. The durat...

23 GLUT1 is the primary glucose transport protein of the cardiovascular system and astroglia. A 24 recent study proposes that caffeine uncompetitive inhibition of GLUT1 results from interactions 25 at an exofacial GLUT1 site. Intracellular ATP is also an uncompetitive GLUT1 inhibitor and 26 shares structural similarities with caffeine suggesting that caffeine acts at the previously 27 character...

Microalgae are a rich source of plant hormones, vitamins, and other substances that can influence physiological metabolism, which in turn affects development, biotic abiotic stress resistance, yield. This study aimed at testing microalgae Planktochlorella nurekis clones obtained by co-treatment with colchicine cytochalasin on four species to check their potential use as biostimulators agricultu...

This study investigates the involvement of actin microfilaments in fibrinogen receptor redistribution and cytoskeletal reorganization that takes place in fully spread, surface-activated platelets. Colloidal gold-labeled fibrinogen (Fgn-Au label) in conjunction with video-enhanced differential interference contrast light microscopy (VDIC) was used to identify fibrinogen binding sites, glycoprote...

Na+-glucose cotransporter (SGLT1) expression and the role of actin in epidermal growth factor (EGF)-induced alterations in glucose transport and brush-border surface area were examined in New Zealand White rabbit jejunal loops. In separate experiments, EGF or EGF concurrent with cytochalasin D, an inhibitor of actin polymerization, was administered to the experimental loop and compared with its...