Author/Editor		Akopian, A; Szikra, T; Cristofanilli, M; Križaj, D
Title		Glutamate-induced Ca2+ influx in third-order neurons of salamander retina is regulated by the actin cytoskeleton
Type		članek
Source		Neuroscience
Vol. and No.		Letnik 138, št. 1
Publication year		2006
Volume		str. 17-24
Language		eng
Abstract		Ligand-gated ion channels (ionotropic receptors) link to the cortical cytoskeleton via specialized scaffold proteins and thereby to appropriate signal transduction pathways in the cell. We studied the role of filamentous actin in the regulation of Ca influx through glutamate receptor-activated channels in third-order neurons of salamander retina. Staining by Alexa-Fluor 488-phalloidin, to visualize polymerized actin, we show localization of filamentous actin in neurites, and the membrane surrounding the cell soma. With Ca(2+) imaging we found that in dissociated neurons, depolymerization of filamentous actin by latrunculin A, or cytochalasin D significantly reduced glutamate-induced intracellular Ca(2+) accumulation to 53+/-7% of control value. Jasplakinolide, a stabilizer of filamentous actin, by itself slightly increased the glutamate-induced Ca(2+) signal and completely attenuated the inhibitory effect when applied in combination with actin depolymerizing agents. These results indicate that in salamander retinal neurons the actin cytoskeleton regulates Ca(2+) influx through ionotropic glutamate receptor-activated channels, suggesting regulatory roles for filamentous actin in a number of Ca(2+)-dependent physiological and pathological processes.
Descriptors		ACTINS AMBYSTOMA ANIMALS BICYCLO COMPOUNDS, HETEROCYCLIC CALCIUM CELLS, CULTURED CYTOCHALASIN D CYTOSKELETON DATA INTERPRETATION, STATISTICAL GLUTAMIC ACID MICROSCOPY, CONFOCAL RECEPTORS, GLUTAMATE RETINA RETINAL GANGLION CELLS THIAZOLES